Engineering Commons^™

On The Mobility Of Small Aperture Telescopes For Initial Orbit Determination And Apparent Magnitude Derivation Of Low Earth Satellites, Jonathan Ian Hernandez

Master's Theses

Maintaining Space Domain Awareness (SDA) of satellites in low Earth orbit (LEO) requires effective methods of tracking and characterization. Optical measurements of these objects are generally sparse due to limited access intervals and high angular rates. Light pollution and geographic obstructions may also preclude consistent observations. However, a mobile small aperture telescope grants the ability to minimize such environmental effects, thereby increasing capture likelihoods for objects within this regime. By enhancing LEO satellite visibility in this way, extensive orbital and visual data are obtainable.

An 8-inch Meade LX200GPS telescope equipped with a Lumenera SKYnyx2-0M CCD camera comprises the system that …

An Analysis Of Camera Configurations And Depth Estimation Algorithms For Triple-Camera Computer Vision Systems, Jared Peter-Contesse

Master's Theses

The ability to accurately map and localize relevant objects surrounding a vehicle is an important task for autonomous vehicle systems. Currently, many of the environmental mapping approaches rely on the expensive LiDAR sensor. Researchers have been attempting to transition to cheaper sensors like the camera, but so far, the mapping accuracy of single-camera and dual-camera systems has not matched the accuracy of LiDAR systems. This thesis examines depth estimation algorithms and camera configurations of a triple-camera system to determine if sensor data from an additional perspective will improve the accuracy of camera-based systems. Using a synthetic dataset, the performance of …

Optimizing A Virtual Human Platform For Depression/Suicide Ideation Identification For The American Soldier, Christina M. Monahan

Master's Theses

Suicide surpassed homicide to be the second leading cause of death among people 10-24 years old in the United States \cite{1}. This statistic is alarming especially when combined with the more than eight distinctly different types of clinical depression among society today \cite{2}. To further complicate this health crisis, let’s consider the current worldwide isolating pandemic often referred to as COVID-19 that has spanned 12 months. It is more important than ever to consider how we can get ahead of the crisis by identifying the symptoms as they set in and more importantly ahead of the decision to commit suicide. …

Characterizing Direction Specific Ganglion Cell Receptor Activation Using A Perturbation Based Decomposition Method, Camila Paola Monchini Moline

Master's Theses

Characterizing postsynaptic current signals in the retina by neuroreceptor activation frequency is important for studying the mechanism of action behind phototransduction of varied visual stimuli. A better understanding could in turn lead to the creation of methods for early detection and prevention of debilitating optical neuropathies, such as glaucoma, age-related macular degeneration, and retinitis pigmentosa. More recent in-vitro and in-vivo studies have aimed to differentiate the effects of various neurotransmitters, such as acetylcholine, GABA, and glutamate, on receiving and processing different types of visual stimuli from the retina into the visual cortex.

The focus of this work will be to …

Assessing The Effects Of Oxaliplatin On An In Vitro Three-Dimensional Human Colorectal Cancer Model, Sabrina Nelson

Master's Theses

Colorectal cancer is the third most common cancer in the United States with a 5-year late-stage survival rate of only 14%. Due to the lack of translation between animal models and clinical trials as well as the inefficacy of many chemotherapeutics in initial clinical trials, researchers are turning to in vitro drug screening models in an effort to mimic the conditions in vivo. This research project aimed to validate an in vitro tumor culture model within a microfluidic device using a clinically relevant chemotherapy drug. The first experiment consisted of a cell density and drug concentration study to determine …

Performance Loss Rate And Temperature Modeling In Predictive Energy Yield Programs For Utility-Scale Solar Power Plants, Katelynn M. Dinius

Master's Theses

The Gold Tree Solar Farm, designed by REC Solar, has a rated output power of 4.5 MW and began operation in 2018 to provide electricity to Cal Poly’s campus. Gold Tree Solar Farm site terrain consists of rolling hills and uneven slopes. The uneven typography results in interrow shading, requiring a modified tracking control algorithm to maximize power production. Predicting a utility solar field’s lifetime energy yield is a critical step in assessing project feasibility and calculating project revenue. The MATLAB-based predictive power model developed for this field overpredicted power in the middle of the day. The purpose of this …

Indoor Positioning Using Synchronized Ultrasonic Ofdma Signals, Julian Bartolone

Master's Theses

This paper proposes a method of short-range indoor localization using differential phase measurements of synchronized two-tone ultrasonic signals in an Orthogonal Frequency Multiple Access (OFDMA) scheme. This indoor positioning system (IPS) operates at an ultrasonic frequency of approximately 40kHz and synchronizes using an infrared signal. The OFDMA scheme allows for a receiver to process the signals from multiple transmitters continuously without the signals interfering with each other. The phases of the signals are measured using Goertzel Filters, allowing for low-complexity frequency content analysis. A MATLAB simulation using the proposed localization method is performed using four transmitter nodes in the corners …

Classifying Electrocardiogram With Machine Learning Techniques, Hillal Jarrar

Master's Theses

Classifying the electrocardiogram is of clinical importance because classification can be used to diagnose patients with cardiac arrhythmias. Many industries utilize machine learning techniques that consist of feature extraction methods followed by Naive- Bayesian classification in order to detect faults within machinery. Machine learning techniques that analyze vibrational machine data in a mechanical application may be used to analyze electrical data in a physiological application. Three of the most common feature extraction methods used to prepare machine vibration data for Naive-Bayesian classification are the Fourier transform, the Hilbert transform, and the Wavelet Packet transform. Each machine learning technique consists of …

Benchmark Testing Of Gold Ribbon Bonds On Thin-Film Microchips With New Gold Ribbon Auto-Bonder, Austin Conrad

Master's Theses

The focus of this document is on the gold ribbon bond testing and creation of a bonding map for the new gold ribbon Auto-Bonder at Keysight Technologies in Santa Rosa, California. The new Auto-Bonder replaces a nearly 50-year-old machine that no longer had any documentation for the original process of thin-film microchip ribbon bonding. The original process was developed in the early 1970s to provide an electrical connection from the top to the bottom of the microchip. The electrical connection takes the place of what would be a via in a modern silicon microchip. Gold wire bonding is a common …

Medial And Lateral Tibiofemoral Contact Forces For Individuals With High Body Mass Index In Gait And Cycling Training, Reymil Fernandez

Master's Theses

The prevalence of knee osteoarthritis, a degenerative joint disease characterized by the degradation of articular cartilage, is correlated with the rise in obesity. The rising rates of obesity in children and adults highlight the need for identifying a sustainable physical activity that promotes fitness while mitigating initiation and progression of osteoarthritis. The objective of this study was to determine an effective rehabilitation and lifelong fitness sustainment exercise regimen that minimize risk of osteoarthritis in individuals with high body mass index (BMI). The aim was to examine knee medial and lateral contact forces in gait and cycling training. Gait at self-selected …

Wi-Fi Sensing: Device-Free In-Zone Object Movement Detection, Nicholas P. Schnorr

Master's Theses

Wi-Fi Sensing is becoming a prominent field with a wide range of potential applications. Using existing hardware on a wireless network such as access points, cell phones, and smart home devices, important information can be inferred about the current physical environment. Through the analysis of Channel State Information collected in the Neighborhood Discovery Protocol process, the wireless network can detect disturbances in Wi-Fi signals when the physical environment changes. This results in a system that can sense motion within the Wi-Fi network, allowing for movement detection without any wearable devices.

The goal of this thesis is to answer whether Wi-Fi …

Triangular Cosserat Point Element Method For Reducing Soft Tissue Artifact: Validation And Application To Gait, Jake Edward Deschamps, Stephen Klisch

Master's Theses

Human motion capture technology is a powerful tool for advancing the understanding of human motion biomechanics (Andriacchi and Alexander, 2000). This is most readily accomplished by applying retroreflective markers to a participant’s skin and tracking the position of the markers during motion. Skin and adipose tissue move independently of the underlying bone during motion creating error known as soft tissue artifact (STA), the primary source of error in human motion capture (Leardini et al., 2005).

(Solav et al., 2014) proposed and (Solav et al., 2015) expanded the triangular Cosserat point element (TCPE) method to reduce the effect of STA on …

Developing A Light Curve Simulation Tool For Ground And Space-Based Observations Of Spacecraft And Debris, Andrew T. Ochoa

Master's Theses

A light curve is a plot of brightness versus time of an object. Light curves are dependent on orbit, attitude, surface area, size, and shape of the observed object. Using light curve data, several analysis methods have been developed to derive these parameters. These parameters can be used for tracking orbital debris, monitoring satellite health, and determining the mission of an unknown spacecraft.

This paper discusses the development, verification, and utilization of a tool that simulates light curve data. This tool models ground-based observations, space-based observations, self-shadowing geometry, tumbling debris, and controlled spacecraft. The main output from the tool is …

Thermal Vacuum Chamber Modification, Testing, And Analysis, Jared C. Lehmann

Master's Theses

This work discusses the modification and analysis of the Blue Thermal Vacuum Chamber (TVAC) located at the Space Environments Lab at California Polytechnic State University, San Luis Obispo. The modified design has a cylindrical test section and can accommodate 6U Cubesats or larger for educational or research purposes. The sizing process for the modified shroud cooling system and modular heating plates is discussed. The modified cooling system uses existing nitrogen plumbing into the chamber and control systems with a new copper shroud. The modified heating system uses modular heater plates, which utilize the existing three heater strips. The modified system …

Testing And Characterization Of Polymer Laminates For Swelling, Absorption, And Cracking, Matthew W. Carlson

Master's Theses

A polymer laminate consisting of multiple layers of proprietary blends of Ethylene Vinyl Alcohol (EVOH) and Thermoplastic Polyurethane (TPU) and used in the construction of air bladders was evaluated for hygroscopic effects driving delamination and multiple layer fragmentation. These air bladders are observed to suffer delamination during a manufacturing process that involves immersion in an alcohol/water solution. A plausible underlying mechanism is differential swelling and absorption by the laminate constituents. Both room and elevated temperature swelling tests were carried out to find the absorption and swelling coefficients of the constituents. These coefficients served as input into a Finite Element Analysis …

Optimization Of Interplanetary Transfer Trajectories Using The Invariant Manifolds Of Halo Orbits, Ryan Yedinak

Master's Theses

Traditionally, two-body dynamics have been used to design orbital trajectories for interplanetary missions using a series of Lambert’s transfers and gravity assists. Although these are reliable methods, they have extremely high fuel requirements, especially for missions to outer planets. From an orbital mechanics perspective, three ways of reducing fuel requirements for these types of missions are utilizing low energy transfer trajectories, applying low thrust engine parameters, and implementing orbit optimization techniques.

The goal of this thesis is to combine low energy transfers created from the dynamics of the Circular Restricted Three-Body Problem (CRTBP) with low-thrust orbit optimization techniques to develop …

Subnational Map Of Poverty Generated From Remote-Sensing Data In Africa: Using Machine Learning Models And Advanced Regression Methods For Poverty Estimation, Lionel N. Hanke

Master's Theses

According to the 2020 poverty estimates from the World Bank, it is estimated that 9.1% - 9.4% of the global population lived on less than $1.90 per day. It is estimated that the Covid-19 pandemic further aggravated the issue by pushing more than 1% of the global population below the international poverty line of $1.90 per day (WorldBank, 2020). To provide help and formulate effective measures, poverty needs to be located as exact as possible. For this purpose, it was investigated whether regression methods with aggregated remote-sensing data could be used to estimate poverty in Africa. Therefore, five distinct regression …

Potential Impact Of Contour Bunds On Diclofenac Removal For Stormwater Control In Rangeland Applications, Braden Alan Whitehead

Master's Theses

Diclofenac (DCF) and other emerging contaminants have been found in environments worldwide. These contaminants may enter the environment due to the application of treated wastewater, biosolids and direct excrement related to veterinary application. Leakage from the soils toward the groundwater is largely controlled by sorption and microbial degradation. Most studies on the environmental fate of DCF have focused on degradation during wastewater treatment processes. However, little is known about their behavior in soil. In this study, the combined effect of adsorption and degradation of diclofenac has been investigated in four (4) 24 ft³ agricultural soil-filled beds designed to mimic …

A Study Of Non-Computing Majors' Growth Mindset, Self-Efficacy And Perceived Cs Relevance In Cs1, Jae Hyuk Yoo

Master's Theses

As the demand for programming skills in today’s job market is rapidly increasing for disciplines outside of computing, CS courses have experienced spikes in enrollment for non-majors. Students in disciplines including art, design and biological sciences are now often required to take introductory CS courses. Previous research has shown the role of growth mindset, self-efficacy and relevance in student success within CS but such metrics are largely unknown for non-majors. In this thesis, we surveyed non-majors in CS1 at Cal Poly, San Luis Obispo during the early and late weeks of the quarter to gain insights on their growth mindset, …

Comparison Of Two Advanced Oxidation Processes For Their Production Of Hydroxyl Radicals And Evaluation Of A Uv/Ozone Aop At Varying Uv Fluence For Treating Diclofenac, Alexandra Cass

Master's Theses

This study explores the efficacy of two advanced oxidation processes for generation of hydroxyl radicals to promote degradation of emerging contaminants. Drought and water shortage have become pressing issues caused by our world’s changing climate. Water reclamation and reuse are increasingly important options for relieving this water stress. Water reuse runs the risk of reintroducing recalcitrant compounds that can accumulate in our bodies and environment. Advanced treatment methods that degrade these compounds are vital to protect our health and the health of the environment while providing necessary water resources. Advanced oxidation processes (AOPs) have shown great promise for removing recalcitrant …

Nonlinear Model Development And Validation For Ball And Plate Control System, Zachary Richter

Master's Theses

Ball and plate balancing control systems are commonly studied due to the complex dynamics associated with the instability of the system in open-loop. For simplicity, mathematical models describing the ball and plate dynamics are often linearized and the effects of complex motion are assumed to be negligible. These assumptions are rarely backed with evidence or explanations validating the simplified form of the dynamical equations of motion. This thesis focuses on developing a nonlinear model that more accurately defines the dynamics of the system, in order to quantify the error of linear and nonlinear models when compared to a Simscape physical …

Development Of A Low-Cost, Photovoltaic-Powered, Automated Water Recovery System, David E. Daley

Master's Theses

An existing water filtration system at the Channel Islands Marine & Wildlife Institute (CIMWI) wastes approximately 25 gallons of water per day rinsing out solid waste under light load. To reduce CIMWI’s water and energy consumption, an automated system was designed and built to recover the rinse water and return it to the existing filtration loop. Models for fluid system requirements, basic energy needs, and photo- voltaic energy generation were created to aid in component selection. Basic sensors and electronics were programmed in Python for use with a Raspberry Pi single board computer to collect and process water recovery data …

Subclinical Atherosclerosis Quantified Through Cumulative Shear Measurement, Margaret Lynne Papka

Master's Theses

With the high mortality rate of cardiovascular disease, it is important to study the early signs. The early detection of cardiovascular disease can lead to saved lives. Currently the most prevalent detection methods are the Framingham Risk Score and the carotid intima media thickness, both of which are insufficient. The necessary tool for early detection requires a uniform quantification system. The stimulus leading to endothelial dysfunction, the most significant predictor of a major adverse cardiovascular event (MACE)—and subsequently subclinical atherosclerosis—is reduced shear stress. Increased surface relative roughness affects the flow profile transition from laminar to turbulent resulting in reduced shear …

Interior Point Optimization Of Low-Thrust Spacecraft Trajectories, Jordan D. Frederiksen

Master's Theses

Low-thrust interplanetary spacecraft trajectory optimization poses a uniquely difficult problem to solve because of the inherent nonlinearities of the dynamics and constraints as well as the large size of the search space of possible solutions. Tools currently exist that optimize low-thrust interplanetary trajectories, but these tools are rarely openly available to the public, and when they are available they require multiple interfaces between multiple different packages. The goal of this work is to present a new piece of low-thrust interplanetary spacecraft trajectory optimization software that is open-source and entirely self-contained so that more people can have access to the ability …

Snr: Software Library For Introductory Robotics, Spencer F. Shaw

Master's Theses

This thesis introduces "SNR," a Python library for programming robotic systems in the context of introductory robotics courses. Greater demand for roboticists has pressured educational institutions to expand robotics curricula. Students are now more likely to take robotics courses earlier and with less prior programming experience. Students may be attempting to simultaneously learn a systems programming language, a library API, and robotics concepts. SNR is written purely in Python to present familiar semantics, eliminating one of these learning curves. Industry standard robotics libraries such as ROS often require additional build tools and configuration languages. Students in introductory courses frequently lack …

Noninvasive Measurement Of Arterial Compliance With A Blood Pressure Cuff Using A Surrogate Arm Bench Top Model For Oscillometric Use, Shane Wilsey

Master's Theses

A surrogate arm model was created that is capable of being used for oscillometry. This model is capable of being used as a bench top model for blood pressure cuff devices. The arm consists of endplates and internal supports that are 3D printed with ABS, a silicone rubber outer sleeve, and interchangeable arteries made from two silicone rubber strips glued together at the edges. The interchangeable arteries have varying compliances that can be used as different inputs for oscillometric testing. A process was established to measure the artery compliances with a curve fit correlation of 0.95. However, testing revealed that …

Integral Boundary Layer Methods In Python, Malachi Joseph Edland

Master's Theses

This thesis presents a modern approach to two Integral Boundary Layer methods implemented in the Python programming language. This work is based on two 2D boundary layer methods: Thwaites' method for laminar boundary layer flows and Head's method for turbulent boundary layer flows. Several novel enhancements improve the quality and usability of the results. These improvements include: a common ordinary differential equation (ODE) integration framework that generalizes computational implementations of Integral Boundary Layer methods; the use of a dense output Runge-Kutta ODE solver that allows for querying of simulation results at any point with accuracy to the same order as …

Minimizing Leakage In Thin Walled Structures Printed Through Selective Laser Melting, Andrew Spencer Yap

Master's Theses

In this project, the scan strategy of selective laser melting (SLM) for thin walled structures was investigated by changing laser parameters and tool path. Producing thin walled structures is difficult due to defects such as warpage and porosity. A layer on the SLM 125 consists of hatch volume, fill contours, and borders, however, for thin walls, hatch volume can become unavailable, resulting in a solely border/fill contour laser tool path.

Three central composite designs (CCD) were created to optimize the laser parameters of borders to minimize leakage rate and porosity. The two factors changed were border laser power and scanning …

A Method For Monitoring Operating Equipment Effectiveness With The Internet Of Things And Big Data, Carl D. Hays Iii

Master's Theses

The purpose of this paper was to use the Overall Equipment Effectiveness productivity formula in plant manufacturing and convert it to measuring productivity for forklifts. Productivity for a forklift was defined as being available and picking up and moving containers at port locations in Seattle and Alaska. This research uses performance measures in plant manufacturing and applies them to mobile equipment in order to establish the most effective means of analyzing reliability and productivity. Using the Internet of Things to collect data on fifteen forklift trucks in three different locations, this data was then analyzed over a six-month period to …

Modeling Action Potential Propagation During Hypertrophic Cardiomyopathy Through A Three-Dimensional Computational Model, Julia Elizabeth Kelley

Master's Theses

Hypertrophic cardiomyopathy (HCM) is the most common monogenic disorder and the leading cause of sudden arrhythmic death in children and young adults. It is typically asymptomatic and first manifests itself during cardiac arrest, making it a challenge to diagnose in advance. Computational models can explore and reveal underlying molecular mechanisms in cardiac electrophysiology by allowing researchers to alter various parameters such as tissue size or ionic current amplitudes. The goal of this thesis is to develop a computational model in MATLAB and to determine if this model can accurately indicate cases of hypertrophic cardiomyopathy. This goal is achieved by combining …