Engineering Commons^™

Design, Test, And Comparison Of A Photovoltaic Thermal Hybrid Solar Collector Utilizing A Thermosiphon, And Theory And Analysis Of Related Predictive Computer Model, Lance Brown

Master's Theses

Design, construction and testing of a photovoltaic thermal collector, or PVT, was completed to determine efficiency improvements of this system compared to a conventional solar panel and to find the thermal energy gained through hot water storage. Flow, driven by density changes from solar radiation, creates a thermosiphon, moving water without the use of a pump and ultimately drawing heat away from the solar panel. This is done to create a more efficient solar panel as well as decreasing potential damage due to high temperatures. Evaluation of electrical efficiency, thermal efficiency and flowrate allow for comparison between other PVT systems. …

Development Of Ex-Situ Accelerated Chemical Stress Test Protocol For Common Anionic Exchange Membrane Chemistries, Michael D. Friend, Michael D. Friend

Master's Theses

The development of sustainably produced hydrogen fuel (“green hydrogen”) is key for the transition to clean energy sources. Green hydrogen is produced via water electrolysis. As with many clean energy sources, one of the major barriers for scaling water electrolysis is cost. A newer category of water electrolysis is Anionic Exchange Membrane (AEM) water electrolysis. AEM electrolysis systems have the potential to cost less as they do not require the expensive precious metal catalysts the current high preforming Proton Exchange Membrane water electrolysis technologies do. However, AEM lifetimes must be long enough to be cost competitive and AEM chemical durability …

Risc-V Gpu Acceleration On Low-Cost Embedded Systems, Fadi M. Alzammar

Master's Theses

The Vortex project from Georgia Institute of Technology was created to provide an open-source hardware and software GPGPU research platform based on RISC-V. Skybox was introduced as an extension to Vortex to provide dedicated support for 3D graphics rendering acceleration as a complete GPU platform. This work presents contributions to the render output unit of Skybox, including the development of a blend unit, cache bypassing mechanisms, and performance monitoring metrics. With these, Skybox has succeeded in its goal of accelerating graphics rendering on RISC-V platforms. This work also establishes a foundation for adapting Vortex to low-cost embedded platforms such as …

Fault Box Modeling Of Dip Slip Faults: A Framework For Fault Box Design And Future Studies, Hailey Pressnell

Master's Theses

The behavior of soils during surface fault rupture is a serious concern in the planning and design of infrastructure that may be located within or near a fault zone. Challenges associated with developing mitigation measures for surface fault rupture include the uncertainty of fault rupture and the variability of fault behavior. Current analytical procedures define surface fault rupture according to the type of fault movement (strike slip, normal or reverse), the amount of displacement on the fault, and the mechanics of the material overlying the fault. The purpose of this thesis is to reconfirm analytical solutions and gain a better …

Analyzing The Safety Effects Of Edge Lane Roads For Motor Vehicle Users, John Yang

Master's Theses

This thesis builds upon a prior study that analyzed the safety effects of Edge Lane Roads (ELRs) within the U.S. context, addressing gaps related to collision, traffic volume, and speed data. An ELR is a roadway configuration that accommodates two-way automobile traffic within a single center lane while providing edge lanes for vulnerable road users (VRUs), i.e., bicyclists or pedestrians. Although the concept of a single shared lane for opposing traffic often raises safety concerns among the public, ELRs have demonstrated potential to control speeds, optimize roadway space, and improve traffic operations on low-volume roads.

To evaluate safety outcomes, this …

Measuring Gait Of Total Knee Arthroplasty Patients Pre-Op And Post-Op Using A Smartphone, Celeste A. Thai

Master's Theses

Motion capture technology is a tool often used in orthopedic applications, including measuring gait dysfunctions. However, gait analysis research focused on total knee arthroplasty (TKA) patients is limited, especially using motion capture systems. This may be due to a multitude of factors, such as inaccessibility to gait labs to the general public, difficulty of travel post-surgery, and overall costs of care and maintenance of motion lab equipment. New emerging novel methods use wearable devices such as smartphones and inertial measurement devices (IMUs) to perform gait assessment and are becoming favorable due to their increasingly ubiquitous nature. One such method using …

Design And Testing Of A Prototype Prosthesis For Pediatric Upper-Limb Transradial Amputees To Provide Adjustable Size And Modular Characteristics, Paul Heli

Master's Theses

This study was conducted to develop a financially accessible body-powered upper-limb prosthetic socket that can be adjusted to maintain fit and function for a growing child with a transradial amputation. The main objectives of the study were to design, manufacture, and test a device that was comfortable, functional, affordable, and adjustable. The socket was designed to be comfortable using global variables controlling the computer-aided design (CAD) model size with user-specific measurements. Comfort was also incorporated using shape-forming of the socket for specific residual limb features. The device was designed to perform the two main functions of suspension, or attachment to …

Development Of A Pressure Sensing System Coupled With Deployable Machine Learning Models For Assessing Residual Limb Fit In Lower Limb Prosthetics, Maxwell D. Lewter

Master's Theses

Lower limb amputations pose significant challenges for patients, with over 150,000 cases annually in the U.S., leading to a high demand for effective prosthetics. However, only 43% of lower limb prosthetic users report satisfaction, primarily due to issues with socket fit, which is critical for comfort, stability, and preventing injury. This study presents a deployable sensing system for potentially real-time monitoring of prosthetic socket fit by using pressure sensors and convolutional neural networks (CNNs) to analyze the pressure distribution within the socket. A novel CNN architecture, utilizing both dilated and strided convolutions, is proposed to effectively capture spatial-temporal patterns in …

Perceptual Hash Based Content Matching, Nicholas Daniel Chenevey

Master's Theses

The proliferation of video content and AI generated imagery has introduced a number of new challenges in content identification and verification. The ability to trace content back to its source has become a critical problem as video content increases both naturally and synthetically through AI generation. This thesis provides the design, analysis, and experimental verification for a perceptual hash based framework aimed at addressing these challenges. Perceptual hashing is a method for encoding the visual content of images into compact and easily comparable binary strings. This process is used as the foundation for content matching in videos and source verification …

The Integration And Validation Of A Class 3b Laser For Stereo Particle Imaging Velocimetry, Jensen Lam

Master's Theses

Particle Imaging Velocimetry (PIV) is a laser flow diagnostic measurement technique used to measure spatial and temporal velocity fields. In an effort to promote experimental aerodynamic research, specifically an entry point for students to learn Particle Imaging Velocimetry, an in-house Class 3B laser PIV system was developed and its experimental results were verified with a Class 4 laser. Both systems were integrated on the Cal Poly Water Tunnel Laboratory. The work emphasizes the application of lasers controlled by a micro-controller to perform microsecond-based pulses and integrating a newly-developed device with an old system consisting of software, cameras, and synchronizers. The …

Design, Manufacturing, And Assembly Of Modular Snake-Like Robotic Arm, Alongside Design And Implementation Of System’S Digital-Twin, Scott Brown

Master's Theses

A unique modular snake-like robotic arm, also referred to as MA\RS – the Modular Arm \ Robotic System - was designed, manufactured, assembled, simulated, and programmed to create a modular robot which could move to a desired end position given the number of links, the position of the end link and the duration of motion. This robotic arm serves as the start of research into a modular space robotic system to be used in low-gravity environments. As such, this project focused on developing the initial design of the robot and its digital twin. The system’s modularity allows for changes to …

An Investigation Into The Use Of Amateur Astronomy Equipment For Optical Orbit Determination Using A Mobile Telescope Platform, Johan C. Govaars

Master's Theses

The process of optical orbit determination has long been in the domain of large organizations and stationary observatories with highly specialized scientific equipment. This thesis seeks to determine not only if satellites can be captured regularly using purely commercial-off-the-shelf (COTS) equipment, but also if initial orbit determinations can be made using that data. Moreover, the use of a mobile telescope platform allows users to circumvent the restrictions of fixed observatories such as low horizon viewing restrictions or existing light pollution.

A completely COTS setup was utilized that included an 8-inch Celestron NextStar 8SE telescope with an f/6.3 focal reducer and …

Cutting Mechanisms And Control Systems Required For Precision Cutting With An Autonomous Lettuce Harvester, Aidan V. Fischer

Master's Theses

43% of California’s vast land is consumed for agricultural production to feed the United States and other nations Lettuce production alone brought in over $3 billion in 2022 in California. Most of the lettuce today is still harvested by hand using large groups of seasonal laborers; however, this has become increasingly difficult with an immigrant labor shortage. The objective of this study was to design a low-cost autonomous lettuce harvester prototype and evaluate the performance of the harvester capable of harvesting romaine lettuce preciously on a raised bed.

The harvester is equipped with an electrohydraulic control system that is used …

Practical Model Of A Labview Controlled Active Magnetic Bearing On A Bently Rotor Kit Validated With Matlab And Msc Adams, Luis Herrera-Delgado

Master's Theses

This thesis aimed to model a rotor supported by an active magnetic bearing (AMB). The magnetic force equation due to a single electromagnet was first derived which served as the basis of AMB modeling. The finalized model utilized Matlab, Simulink, and MSC Adams to simulate a rotor supported by an AMB. Matlab and Simulink were used to model the AMB control system and actuator output. MSC Adams was used to capture the dynamics of a flexible rotor. This model was verified by comparing the model’s simulated vibration to real vibration data measured from a modified Bently Nevada rotor kit equipped …

Peer Collaborative Networks In Undergraduate Computing Classrooms, Noah T. Ravetch

Master's Theses

Peers are an invaluable resource for students at undergraduate universities. Many factors can impact how students form connections, some of which are tied to the students’ identities. While social networks have been studied in the context of universities, little research has been done specifically about peer collaboration and even less in the context of computer science classes. Our research aims to gain an understanding of how peer networks form in computing classes and the effect of being involved in one on students’ academic performances. We collected survey data (n = 139) about students’ peer collaborative behaviors in computer science classes. …

Performance Of Multi-Composite Materials With Corrugated And Cell Geometries Under Low-Velocity Impact, Lukas S. Kolbl

Master's Theses

Composite structures have demonstrated great potential to improve mechanical performance in various applications, including ballistics protection. This study demonstrates that the integration of geometrically optimized composites into core-face sheet assemblies provide great impact resistance. The research investigated the performance of two composite manufacturing methods under low-velocity impact through residual strength and damage comparisons. Corrugated core composites were produced with traditional manufacturing methods, namely compression molding, using twelve stacking sequences. These stacking sequences were chosen to represent four laminate groups, where a unique fiber orientation scheme was employed across three laminate thicknesses (6, 8, and 12 layers). In contrast, honeycomb and …

Finite Element Analysis And Verification Of Transverse Mechanical Properties Of Generally Cylindrical Orthotropic Constitutive Modeling Of 3-Phase Nanocomposite Unit Cell, Christopher J. Hawkins

Master's Theses

Fiber-reinforced composites are increasingly popular due to their specific strength and stiffness, making them ideal for high-performance applications. However, these materials primarily exhibit superior properties in-plane, while their out-of-plane characteristics remain comparatively weaker. Previous research has shown that the most effective method to enhance out-of-plane properties involves the incorporation of carbon nanotubes. Experimental tests have demonstrated significant improvements in properties such as tension, flexural, short beam shear, and fracture toughness. Alongside these experimental studies, analytical equations have been developed to predict the behavior of these composites under various loading conditions, including tension, bending, shear, and fracture. Existing models primarily address …

Bonsai Merkle Tree Streams: Bulk Memory Verification Unit For Trusted Program Verification System, Richard J. Rios

Master's Theses

Today, all modern computing systems are undoubtedly vulnerable to numerous types of attacks that could be targeted toward any layer of the system from dedicated hardware to highly abstracted software. Unfortunately, many devices and systems naturally contain inadequately protected components or software modules that un- dermine their security as a whole. Additionally, security is heavily variable system to system, and has a huge dependence on adequate implementation and ongoing support from device and software manufacturers. To address these various security issues in a very general way, TrustGuard, a containment security system utilizing an external device called the Sentry that would …

Photophoretic Optical Particle Trapping Improvements Using Beam Reflection, Ian A. Garcia, Xiaomin Jin Phd., Kun Hua Phd.

Master's Theses

Current research has shown that photophoretic optical trapping (POT) is a promising method for creating true three-dimensional holograms. A landmark study by Smalley et. al. at BYU was able to generate a full hologram within a 2 cm edge cube with remarkable success. However, a key drawback to this method is its poor ability to hold trapped particles within the focal point of the laser for an extended period of time. An investigation from our group presented at SPIE Photonics West 2023 sought to improve these results by varying the focal length of the trapping and the wavelength of the …

Investigating The Conversion Of A Signalized Intersection To A Turbo Roundabout, Vyshnavi P. Shetty

Master's Theses

Turbo roundabouts are multilane roundabouts that utilize a spiral design with raised lane dividers to guide traffic flow effectively. While they have seen widespread use in Europe, California is the second state in the US (after Florida) to have installed a turbo roundabout. Turbo roundabouts separate the ingress and circulating lanes. The concept was first proposed and implemented in the Netherlands to address safety concerns and improve traffic flow efficiency on conventional multilane roundabouts.

This research evaluates the first-ever turbo roundabout in California and compares its safety and operational performance with the previously existing 4-legged signalized intersection. The research team …

Techno-Economic Analysis Of Waste Plastic Gasification, Henrik Don-Yor Ketting

Master's Theses

The increasing generation of plastic waste and its environmental impact has driven interest in alternative disposal methods such as gasification. This study presents a techno-economic analysis of the gasification of waste plastics, specifically polypropylene (PP) and polyethylene (PE), to produce syngas. A two-stage process—thermal decomposition followed by steam reforming—was simulated using Aspen Plus. The simulation results were validated against experimental data available in the literature. The economic analysis was conducted by estimating the capital and operating costs of the gasification plant, considering factors such as feedstock costs, energy requirements, and syngas purification systems. Net Present Value Calculations were used to …

Experimental And Numerical Investigation Of Droplet Dynamics In Microscale Systems: The Influence Of Surfactants And Nanoparticles On Environmental Applications, Negin Bahadori

Master's Theses

Emulsions are suspensions of droplets dispersed into an immiscible liquid phase, with at least a water phase and an oil phase. The capability to incorporate both hydrophilic and hydrophobic components makes emulsions amenable to a variety of applications, such as bilgewater treatment and oil recovery. To optimize bilgewater treatment or oil recovery, many aspects must be considered, such as the effect of emulsion stability, the wetting conditions and, more in general, the possibility to characterize droplet’s behavior over static or dynamic conditions. This thesis investigates the roles of surfactants and nanoparticles in understanding droplet behavior in oil-water systems, with a …

Machine Learning-Driven Process Analysis And Optimization In Solid-State Welding And Fusion-Based Additive Manufacturing, Radif Uddin Ahmed

Master's Theses

In the modern era of advanced manufacturing, optimizing process parameters is pivotal in ensuring the quality and reliability of sophisticated component fabrication. This study presents a novel, data-driven approach to parameter optimization in two cutting-edge manufacturing techniques: Friction Stir Welding (FSW) and Laser Powder Bed Fusion (LPBF). By leveraging machine learning methodologies, this research addresses the critical challenge of efficiently determining optimal process parameters, a task traditionally relying on time-consuming and resource-intensive trial-and-error methods. This study will lead to a robust data-driven framework for process analysis of more advanced manufacturing techniques like the Additive Friction Stir Deposition (AFSD) process. Friction …

A Novel Reinforcement Learning Method For Efficient Cross-Training Between Real And Simulated Robots, Zhonglin Liang

Master's Theses

Training reinforcement learning policy in a simulated environment can be a go-to choice for many research topics, as a simulated environment provides flexibility and costs less than building a physical environment for training. However, policy trained in a simulated environment often fails to transfer to the real environment for problems that have a more complex dynamics. As the solution, Sim2Real was proposed and it categorizes techniques that improve the performance of the transfer from simulation to reality. Sim2Real is an area of study that focuses on utilizing simulation data to train models that can apply to real world environment. It …

Effect Of Specimen Size On The Tensile Properties Of Selective Laser Melted Ti-6ai-4v, Timothy L. Tan

Master's Theses

Metal additive manufacturing (MAM) is a burgeoning industry. It is capable of manufacturing metal components with fine, intricate features and enables localized microstructural control. Due to its fine resolution and compatibility with common engineering alloys, selective laser melting (SLM) is one particular MAM process popular in academia and industry. The biomedical and aerospace industries have shown exceptional interest in the capabilities of SLM with the alloy Ti-6Al-4V. Because SLM Ti-6Al-4V components are aimed for use in critical applications, it is necessary to understand how SLM processing characteristics affect final part performance. One characteristic of SLM Ti-6Al- 4V that requires further …

Enhancing Cross-Cultural Communication In Low-Resource Language Conversational Agents, Hardi V. Trivedi

Master's Theses

Recent advancements in natural language processing (NLP) and large language models (LLMs) have facilitated the development of systems capable of generating human-like responses across a wide range of tasks. However, the majority of research has focused predominantly on English, overlooking the vast linguistic diversity globally. For true global inclusivity, extending research to other languages is crucial, particularly as it can significantly benefit various sectors such as business, healthcare, government, and education. A major challenge in this expansion is the scarcity of digital data available and the limited number of pre-trained models for low-resource languages. Our research specifically addresses these challenges …

Hypoxic Incubator: Improving Robustness/Reliability And Demonstrating Physiological Efficacy, Damon Dennis Tan

Master's Theses

The Microphysiological Systems Laboratory aims to develop colorectal cancer tumor models under a hypoxic environment to assess model response to pharmaceutical compounds in vitro. To perform relevant studies, researchers have attempted to use different hypoxic inducing strategies such as a nitrogen pod and hypoxic incubator to recreate in vivo physiological responses to hypoxia. However, studies would be interrupted due to incubator functionality failure. To ensure successful and physiologically relevant studies, I improved and verified the robustness and reliability of a hypoxic incubator previously designed and manufactured in the lab. Through the testing and iterating design processes, I engineered and implemented …

3d Printed Microfluidic Fabrication Methodology, Characterization, Mechanical Design, And Applications In Electrostatic Artificial Muscles And Benthic Microbial Fuel Cells, Terak B. Hornik

Master's Theses

The fabrication of microfluidic devices often requires specialized methods. The development of these methods requires careful characterization and understanding of the processes involved. Using primarily PolyJet 3D printing technology, microfluidics offers a wide scope of applications such as microfluidic benthic microbial fuel cells (MBMFCs) and electrostatic artificial muscles. MBMFCs benefit from the confinement of the microbes resulting in close proximity between the electrode and the organisms. Using a modular design called the Sponge, assembly and upscaling is possible. Electrostatic artificial muscles benefit from a microfluidic approach due to the non-linearity of electrostatic attraction creating disproportionate benefits when miniaturized. When designed …

Hardware Control Unit For Trusted Program Verification System, Jake Owen Alt

Master's Theses

Trust in the underlying hardware is the foundational step towards trusting the correctness and integrity of a software application. However, verifying that today's extremely complex processors work exactly as intended has not been feasible, as evidenced by several recent hardware bugs. Trustworthy, formally verified processors currently forego intricate performance enhancements such as out-of-order execution, hampering them substantially versus their less secure counterparts.

The Containment Architecture with Verified Output (CAVO) system solves this problem by isolating the host system and requiring the result of each instruction to be validated by a small, trusted hardware module called the Sentry. Any transmissions to …

Dynamic Maze Puzzle Navigation Using Deep Reinforcement Learning, Luisa Shu Yi Chiu

Master's Theses

The implementation of deep reinforcement learning in mobile robotics offers a great solution for the development of autonomous mobile robots to efficiently complete tasks and transport objects. Reinforcement learning continues to show impressive potential in robotics applications through self-learning and biological plausibility. Despite its advancements, challenges remain in applying these machine learning techniques in dynamic environments. This thesis explores the performance of Deep Q-Networks (DQN), using images as an input, for mobile robot navigation in dynamic maze puzzles and aims to contribute to advancements in deep reinforcement learning applications for simulated and real-life robotic systems. This project is a step …