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3D Printed Fixed Wing Aircraft Competition
Get PDFCal State LA and Arlington University, Texas are hosting the same 3D printed, fixed wing aircraft competition for 2025. Cal Poly requires a competitive plane that can adhere to each rule and be piloted remotely to achieve the longest time in the air. The plane must utilize solely 3D printing technology for the wings, body, and all other structures. The only off-the-shelf components can be the motor and electronics, as well as mechanical devices such as hinges
Field Deployable Mobile Manipulator for Autonomous Apple Harvesting
Get PDFIncreasing labor costs and agricultural demands have created a need for automated apple harvesting. However, automated apple harvesting via robotic manipulation must overcome certain challenges to be an effective and efficient method. First, the system must compete with or perform better than manual human labor. Second, it must safely and accurately navigate an apple orchard autonomously. Third, the robotic manipulator must be able to securely grasp and pick apples without causing damage. To address these challenges, this project utilizes a Husky UGV equipped with a 2D LiDAR sensor, an RGB-D camera, an IMU, an OpenManipulator-X robot arm, and a soft robotic gripper with tactile sensing. Incoming data from the LiDAR sensor and the odometry are processed using SLAM algorithms to enable the robot to map its environment in real time. Then, localization algorithms such as Adaptive Monte Carlo Localization integrate LiDAR and odometry data to precisely position the robot within the map. Using this localization, the robot navigates to each apple tree using the NAV2 stack. Meanwhile, the RGB-D camera data, in combination with YOLOv3 computer vision algorithms, allows the system to detect and locate apples. Finally, the soft robotic gripper samples each apple grasp using force-resistive sensors and analog-to-digital conversion. A convolutional neural network, trained on a custom-collected dataset, classifies each grasp to ensure apples are only harvested under suitable conditions. This complete system is powered by an onboard battery pack with an approximate runtime of 4 hours. This project explores the many subfields of robotics. It demonstrates the successful application of autonomous navigation and robotic manipulation alongside signal processing, sensor integration, and computer vision to enable efficient apple harvesting
The Chumash War of 1824: Revolution and Counterrevolution in the California Missions Santa Inés, Santa Barbara, and La Purísima
Get PDFIn 1824, the Indigenous Chumash of Missions Santa Inés, Santa Barbara, and La Purísima de Concepción went to war against the settler-colonial system that bonded them to the mission lands and forced labor regime demanded by the Spanish Franciscan missionaries and compelled by Mexican military force in Alta California. The conflict lasted months and included violent battles and skirmishes at all three missions, the militant occupation and reclamation of La Purísima, a mass exodus to the interior of the territory, and the subsequent counterrevolutionary collaboration of the Spanish missionaries and Mexican military to return many (but not all) of the Chumash to the missions. In this thesis, I argue that the actions of the Chumash throughout the conflict, available through multiple archival and oral history accounts, show a people engaged in a revolutionary war for autonomy against the settler-colonial mission system. The collective action of the Chumash in 1824 created a deep fissure in the California Mission system at a time of political tumult and radical redefinition during Alta California’s early Mexican period and helped feed the intertribal coalition of Indigenous resistance in the interior of the territory. The revolutionary Chumash contributed to the instability of the settler-colonial system and partly compelled the new Mexican government’s pragmatic decision to formally end the mission system through secularization less than ten years later. This thesis attempts to place the Chumash War of 1824 in this broader context of the Age of Revolutions, New Mission History, and the legacy of genocide of Indigenous Californians in the hopes of reexamining the California Missions in pedagogy and popular historical memory by illustrating the destructive role they played in the lives of Indigenous peoples, and the agency and autonomy that the Chumash asserted to remove themselves from the yolk of the settler-colonial California Mission system
Aluminum Boat Rotation Fixture
Get PDFAluminum fishing boats are widely used for various water-based activities, including fishing, transportation, and recreation. Their lightweight construction makes them ideal for maneuverability, particularly in regions like Australia. However, the manufacturing process presents challenges, specifically the need to weld both the interior and exterior seams of the hull. As the boat’s weight increases during assembly, flipping it becomes difficult and potentially hazardous. Traditional methods such as cranes or forklifts are inefficient and pose safety risks. To address this, our team developed a rotating fixture that secures the boat at two connection points, one at the bow and one at the stern, and uses a gearbox to rotate the boat safely and efficiently
Study on the Application of Smart Electric Meters for Secondary Voltage Protection
Get PDFThe 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 done on how the implementation of these devices can be used for data collection, grid optimization, and fault prediction
Characterization of Indoor Air Quality and Thermal Comfort of University Classrooms
Get PDFIndoor air quality (IAQ) significantly affects cognitive performance, yet many older buildings at Cal Poly, such as Building 20, struggle to maintain healthy indoor environments due to outdated ventilation systems. This thesis aims to identify issues and provide suggestions on how we can improve the learning environment to improve student success within Building 20. Temperature, relative humidity, and carbon dioxide (CO2) concentration inside Building 20 were measured from January to April 2025. To determine the effects of different ventilation strategies, a model of Building 20, room 128, was developed and validated using DesignBuilder. Additionally, ventilation rates were measured and compared to a non-linear regression model that was developed. We found that CO2 levels exceeded 1000 ppm everyday with occupancy — a concentration that hinders cognitive functions. Temperature and relative humidity levels varied considerably and were not in the comfort zone for 85.7% of the monitoring time. This shows that students routinely face inconsistent conditions that hinder their learning. Analysis concludes that Building 20 does not have adequate ventilation to support a consistent and productive learning environment. Ventilation within Building 20 needs to be increased to support continued learning at Cal Poly
Piezoelectric Actuator Driver System
Get PDFThis work presents the design, fabrication, and testing of a high-voltage piezoelectric actuator driver system purposed for integration into defense and aerospace precision motion control applications, particularly those in laser optics. The core challenge addressed was the mismatch between the standardized 28V DC power bus used in military systems and the significantly higher voltage requirements of piezoelectric actuators. Existing commercial drivers were evaluated and found unsuitable for field deployment due to inadequate ruggedness, excessive complexity, or power limitations. Consequently, a modular system architecture was designed featuring four independent driver channels, each using a high-voltage, high-current linear amplifier topology to scale low-voltage analog inputs into single-ended outputs up to 150V with minimal distortion. Several supporting subsystems were developed, including a 28V to 150V boost converter, a programmable reference voltage generator, onboard current/voltage sensing, and RS-232 serial telemetry, control, and configuration. The hardware was fabricated using multi-layer PCBs, high thermal-capacity layout strategies, and shielded coaxial connectors to ensure signal integrity and EMI resilience. A versatile mechanical enclosure was designed for demonstration purposes that integrates with the system’s fans, LEDs, connectors, etc. Hardware testing confirmed the driver’s ability to deliver up to 150mA per channel, maintain voltage regulation under load, and meet minimum signal bandwidth and slew rate requirements. Simulations and lab test results closely align, validating the design approach and confirming the system\u27s technical viability. While the thermal performance of the boost inductor requires further study and improvement, the prototype met all design targets and offers a strong foundation for future enhancements. This effort demonstrates the feasibility of a compact, rugged, high-voltage piezoelectric actuator driver tailored for next-generation mission-critical control systems
Identifying Interchromosomal Interactions Using a Graph-Based Computational Pipeline
Get PDFCurrent computational tools for analyzing chromatin organization are mainly focused on intrachromosomal interactions, despite growing evidence that suggests long-range interactions across chromosomes contribute to transcriptional regulation and disease development. This thesis aims to address this gap in interchromosomal genome analysis, presenting a robust computational pipeline that identifies a clique (i.e., a subgraph) of highly interacting trans-chromosomal regions anchored at a user-specified seed genomic locus. A weighted interaction network is constructed from an input Hi-C contact matrix, a widely used experimental assay for measuring genome-wide chromatin interactions. We model this input contact matrix as a graph and devise three different strategies to computationally find biologically important cliques: (1) a greedy heuristic for efficient local exploration, (2) a simulation-based random walk with restarts, and (3) an analytical formulation of the same random walk process. To validate the performance of this pipeline, we focus on TTN, a key muscle gene whose splicing is essential for human heart development. Hi-C data from wild-type and TTN promoter knockout cardiomyocytes are used to compare structural differences in TTN\u27s long-range interactors. Though sparse contacts in the knockout data limit definitive comparison, cliques built from the wild-type matrix reveal loci with strong gene correlation. We further design several different background models to statistically assess the significance of these interactions. Our results highlight the effectiveness of network-based methods in uncovering functionally relevant interchromosomal interactions and lay the groundwork for future analyses
Comparing the Work-life Balance and Stress at General Contractors and CM Agencies
Get PDFThe struggle for a work-life balance has become a significant issue in the construction industry, resulting in personal and organizational challenges. This paper will compare work-life balance and stress between industry professionals working at a CM agency and those at a general contractor. A CM agency is responsible for overseeing the construction project alongside the owner by providing planning, cost estimation, scheduling, and quality assurance. In contrast, the general contractor is responsible for managing the day-to-day operations on-site. A survey was distributed to both types of construction firms to collect data about work hours, work-life balance, stress, and biggest stressors. The survey includes a section for participants who have worked at both a CM agency and a general contractor, allowing them to indicate which company had the more favorable work-life balance and less stress. An analysis of the data collected in the survey reveals that work-life balance is more favorable at a CM agency, resulting in lower stress levels for employees. The findings from this survey will assist companies in improving employees’ work-life balance and well-being
Exploration of Mental Health Stressors and Proposing Interventions among Heavy-Civil Construction Workers
Get PDFThe mental health of heavy civil construction workers is an often-overlooked issue. Long hours, job insecurity, physically demanding work, and workplace culture contribute to significant stress, anxiety, and other mental health challenges among workers in this industry. This research aimed to assess the mental health conditions of heavy civil construction workers, identify key stressors, and propose effective intervention strategies to improve overall well-being. Using a combination of surveys and interviews, this study gathered both quantitative and qualitative data to gain a comprehensive understanding of workers’ mental health. The surveys provided broad insights into common stressors and overall mental health of heavy civil workers while interviews deepened the understanding of personal experiences and coping mechanisms. Important trends, correlations, and potential risk factors that impact workers’ psychological well-being were identified through detailed content and theme analysis of the gathered surveys’ and interviews’ data. The findings indicated that many construction workers experience high levels of stress due to workplace demands and a lack of mental health support. Various intervention strategies have been suggested to address mental health issues. By addressing these challenges, construction companies can improve worker morale, productivity, and job satisfaction while reducing safety risks