Engineering Commons^™

Speaker Prototyping Design, Andrew Lathe

Undergraduate Honors Theses

Audio design is a pertinent industry in today’s world, with an extremely large market including leaders such as Bose, Harman International, and Sennheiser. This project is designed to explore the processes that are necessary to create a new type of product in this market. The end goal is to have a functioning, high–quality set of speakers to prove various concepts of design and prototyping.

The steps involved in this project go through the entire design process from initial choice of product to a finished prototype. Processes include the selection of outsourced components such as drivers and necessary connectors. The design …

Technology Aiding In Neonatal Lung Developmental Care, Megan Kirk

Undergraduate Honors Theses

In this paper, old as well as new technological findings to decrease premature infant mortality are reviewed. This paper discusses fetal development throughout pregnancy from conception to full-term status as well as fetal lung development specifically from conception until full-term status. Several ideas to rapidly develop and mature fetal lungs are discussed such as mothers ingesting artificial surfactant supplements, either independently or coupled with antenatal corticosteroids, as well as intra-amniotic instillation prior to 28 weeks gestational. Drawbacks regarding these two are mentioned as well such as the fetus’s lungs not being mature enough to use the artificial surfactant leading into …

Exploring The Variability In The Gray Scale Imaging Process Of Asphalt Samples, David Oluwawade Olatunji

Civil Engineering Undergraduate Honors Theses

Gray scale image analysis is a powerful tool for testing asphalt concrete materials. From material composition to surface properties, gray scale analysis has shown evidence as a non-invasive way to obtain information from asphalt samples. Casillas et al. used a gray scale analysis to measure the Representative Volume Element of three asphalt sample geometries to understand the minimum size at which an asphalt sample is representative of a larger homogeneous mixture [1]. While the gray scale analysis used in this experiment yielded results, there were unknown factors in the image capturing process. Particularly, not much was known about the effect …

Racial Diversity In Aviation, Lindsay Stevenson, Haydee M. Cuevas, Katie S. Kirkpatrick

Student Works

Commercial aviation has grown rapidly since the 1950s yet racial diversity in the aviation workforce has showed little progress. To explore this issue, this archival study was conducted to examine the representation of Black individuals in aviation occupations and other specialized professions from 2009 to 2018. Data were obtained from the American Community Survey using Public Use Microdata Sample from the United States Census Bureau. The frequency count and percent were calculated each year for each occupation by race (White or Black). Five aviation occupations were selected for comparison: aircraft pilot and flight engineer; air traffic controller and airfield operations …

An Exploratory Study Of Pulse Width And Delta Sigma Modulators, Logan B. Penrod

Master's Theses

This paper explores the noise shaping and noise producing qualities of Delta-Sigma Modulators (DSM) and Pulse-Width Modulators (PWM). DSM has long been dominant in the Delta Sigma Analog-to-Digital Converter (DSADC) as a noise-shaped quantizer and time discretizer, while PWM, with a similar self oscillating structure, has seen use in Class D Power Amplifiers, performing a similar function. It has been shown that the PWM in Class D Amplifiers outperforms the DSM [1], but could this advantage be used in DSADC use-cases? LTSpice simulation and printed circuit board implementation and test are used to present data on four variations of these …

Video Based Automatic Speech Recognition Using Neural Networks, Alvin Lin

Master's Theses

Neural network approaches have become popular in the field of automatic speech recognition (ASR). Most ASR methods use audio data to classify words. Lip reading ASR techniques utilize only video data, which compensates for noisy environments where audio may be compromised. A comprehensive approach, including the vetting of datasets and development of a preprocessing chain, to video-based ASR is developed. This approach will be based on neural networks, namely 3D convolutional neural networks (3D-CNN) and Long short-term memory (LSTM). These types of neural networks are designed to take in temporal data such as videos. Various combinations of different neural network …

Towards On-Device Detection Of Sharks With Drones, Daniel Moore

Master's Theses

Recent years have seen several projects across the globe using drones to detect sharks, including several high profile projects around alerting beach authorities to keep people safe. However, so far many of these attempts have used cloud-based machine learning solutions for the detection component, which complicates setup and limits their use geographically to areas with internet connection. An on-device (or on-controller) shark detector would offer greater freedom for researchers searching for and tracking sharks in the field, but such a detector would need to operate under reduced resource constraints. To this end we look at SSD MobileNet, a popular object …

Improvement Of Labyrinth Seal Leakage Rates Using Additive Manufacturing, Austin L. Gasbarra

Master's Theses

The growing popularity of additive manufacturing in commercial applications has al- lowed for new ideas and new ways of thinking when designing components. Further optimization at the component level is possible, though powder metallurgy is in its infancy. This study explores the possibility of using additive manufacturing to develop better labyrinth seals in turbomachinery. Labyrinth seals have a torturous fluid path with high losses, thus limiting the amount of fluid leakage. These types of seals can be non-rotating, allowing them to better take advantage of the additive manufacturing process due to the absence of rotating stresses. Labyrinth seal performance is …

Interplanetary Trajectory Optimization With Automated Fly-By Sequences, Emily Ann Doughty

Master's Theses

Critical aspects of spacecraft missions, such as component organization, control algorithms, and trajectories, can be optimized using a variety of algorithms or solvers. Each solver has intrinsic strengths and weaknesses when applied to a given optimization problem. One way to mitigate limitations is to combine different solvers in an island model that allows these algorithms to share solutions. The program Spacecraft Trajectory Optimization Suite (STOpS) is an island model suite of heterogeneous and homogeneous Evolutionary Algorithms (EA) that analyze interplanetary trajectories for multiple gravity assist (MGA) missions. One limitation of STOpS and other spacecraft trajectory optimization programs (GMAT and Pygmo/Pagmo) …

Personality And Mood For Non-Player Characters: A Method For Behavior Simulation In A Maze Environment, Noah L. Paige

Master's Theses

When it comes to video games, immersion is key. All types of games aim to keep the player immersed in some form or another. A common aspect of the immersive world in most role-playing games -- but not exclusive to the genre -- is the non-playable character (NPC). At their best, NPCs play an integral role to the sense of immersion the player feels by behaving in a way that feels believable and fits within the world of the game. However, due to lack of innovation in this area of video games, at their worst NPCs can jar the player …

Emergency Landing And Guidance System, Joseph Alarid

Master's Theses

Every year there are thousands of aviation accidents along with hundreds of human deaths that happen around the world. While the data is sparse, it is well documented that many of these happen from emergency landings gone awry. While pilots can generally make great landings in clear daytime conditions, they are significantly handicapped when it comes to landing at night or amongst poor visibility conditions.

Due to the nature of this problem and some of the large scale advances in software technology we propose a solution that provides a significant improvement from the status quo. Using transfer learning on neural …

Iot Camera System For Monitoring Strawberry Fields, Simon Schoennauer

Master's Theses

A wireless imaging system for monitoring strawberry fields provides enough quality image data for computer vision algorithms to make meaningful yield predictions. This report contains a design for a wireless sensor network modified with mesh networking techniques to extend coverage range and a solar energy harvesting system to improve sensor node lifetime. A two hop system with six nodes is implemented in a laboratory environment validating the communication systems integrity over an 800’ range. Moving from a primary battery system to solar energy harvesting increases the module lifetime indefinitely.

Numerical Analysis Of A Circulation Control Wing, Luke W. Bodkin

Master's Theses

The objective of this thesis was to develop an experimental method to research circulation control wings using numerical analysis. Specifically, it is of interest to perform 3D wind tunnel testing on a circulation control wing in the Cal Poly Low Speed Wind Tunnel (CPLSWT). A circulation control wing was designed and analyzed to determine the feasibility of this testing.

This study relied on computational fluid dynamics (CFD) simulations as a method to predict the flow conditions that would be seen in a wind tunnel test. A CFD simulation was created of a wing model in a wind tunnel domain. Due …

A Novel Method To Commercialize Medical Devices Initially Developed At California Polytechnic State University San Luis Obispo, Christina Grigorian

Master's Theses

California Polytechnic State University, San Luis Obispo is a university that encourages students to approach learning hands-on. As such, there is cutting-edge technology being developed by students in all departments on campus. Being that the university possesses an outstanding biomedical engineering department, there are groundbreaking medical devices that students are creating at Cal Poly SLO. These are devices that can better the lives of individuals suffering from ailments or fulfill needs in the medical industry. Subsequently, it is vital that these devices make it out of campus laboratories and into the hands of consumers. In order to move a product …

Analysis Of Electroanatomic Mapping System Accuracy Using X-Ray Reconstruction Of Electrode Locations In A Porcine Animal Model, Hana Boudlali

Master's Theses

Fluoroscopy is considered the gold standard for locating catheters during cardiac electrophysiology (EP) procedures. However, fluoroscopy emits ionizing radiation which can lead to adverse health effects when exposed to in high doses (World Health Organization, 2016). Electroanatomic mapping (EAM) systems display the three-dimensional location of EP catheters and measure the local electrical activity of the heart. They can minimize a physician’s reliance on fluoroscopy and can help reduce radiation exposure during a case (Casella, 2011).

EAM systems are diagnostic medical devices that inform the placement of ablation therapy and must accurately locate catheters to be deemed safe. Test methods to …

A Protocol For Achieving Adherent Cell Culture Within A Microfluidic Device, Tarra Danielle Sanders

Master's Theses

The goal of this study is to design a protocol for the adherent cell culture within a novel microfluidic device. Microscale cell culture protocols were developed for loading cells using poly-L-lysine to enhance adherent cell culture of murine derived NIH 3T3 fibroblasts. This work sought to develop a method for adherent microculture by examining various sterilization, surface treatment, and seeding techniques. Using a vacuum suction loading technique, air plasma treatment and a poly-L-lysine surface treatment adherent cell culture was observed within the device. The work presented here is part of a collaborative effort that aims to develop protocols for the …

Spacecraft Trajectory Optimization Suite (Stops): Design And Optimization Of Multiple Gravity-Assist Low-Thrust (Mgalt) Trajectories Using Modern Optimization Techniques, Michael G. Malloy

Master's Theses

The information presented in the thesis is a continuation of the Spacecraft Trajectory Optimization Suite (STOpS). This suite was originally designed and developed by Timothy Fitzgerald and further developed by Shane Sheehan, both graduate students at California Polytechnic State University, San Luis Obispo. Spacecraft utilizing low-thrust transfers are becoming more and more common due to their efficiency on interplanetary trajectories, and as such, finding the most optimal trajectory between two planets is something of interest. The version of STOpS presented in this thesis uses Multiple Gravity-Assist Low-Thrust (MGALT) trajectories paired with the island model paradigm to accomplish this goal. The …

B-Plane Targeting With The Spacecraft Trajectory Optimization Suite, Jared Graef

Master's Theses

In interplanetary trajectory applications, it is common to design arrival trajectories based on B-plane target values. This targeting scheme, B-plane targeting, allows for specific target orbits to be obtained during mission design. A primary objective of this work was to implement B-plane targeting into the Spacecraft Trajectory Optimization Suite (STOpS). This work was based on the previous versions of STOpS done by Fitzgerald and Sheehan, however STOpS was redeveloped from MATLAB to python. This updated version of STOpS implements 3-dimensional computation, departure and arrival orbital phase modeling with patched conics, B-plane targeting, and a trajectory correction maneuver. The optimization process …

Incorporating Shear Resistance Into Debris Flow Triggering Model Statistics, Noah J. Lyman

Master's Theses

Several regions of the Western United States utilize statistical binary classification models to predict and manage debris flow initiation probability after wildfires. As the occurrence of wildfires and large intensity rainfall events increase, so has the frequency in which development occurs in the steep and mountainous terrain where these events arise. This resulting intersection brings with it an increasing need to derive improved results from existing models, or develop new models, to reduce the economic and human impacts that debris flows may bring. Any development or change to these models could also theoretically increase the ease of collection, processing, and …

Understanding The Effects Of Long-Duration Spaceflight On Fracture Risk In The Human Femur Using Finite Element Analysis, Keyanna Brielle Henderson

Master's Theses

Long-duration spaceflight has been shown to have significant, lasting effects on the bone strength of astronauts and to contribute to age-related complications later in life. The microgravity environment of space causes a decrease in daily mechanical loading, which signals a state of disuse to bone cells. This affects the bone remodeling process, which is responsible for maintaining bone mass, causing an increase in damage and a decrease in density. This leads to bone fragility and decreases overall strength, posing a risk for fracture. However, there is little information pertaining to the timeline of bone loss and subsequent fracture risk.

This …

Impact Of Soil Properties On Removal Of Emerging Contaminants From Wastewater Effluent During Soil Aquifer Treatment, Lauren N. Riley

Master's Theses

This study evaluates soil properties that impact the effectiveness of soil aquifer treatment (SAT) as a polishing step to the remove two classes of ECs from wastewater effluent: pharmaceuticals and personal care products (PPCPs), and engineering nanomaterials (ENMs). In recent years, it has been determined that elevated levels of emerging contaminants (ECs) are being released into the environment with wastewater effluent. ECs are proven to cause adverse environmental and health effects as a result of long-term exposure. It is important to evaluate sustainable solutions to improve the current methods of wastewater treatment to address these ECs.

Soil aquifer treatment (SAT) …

Finite Element Analysis Of Total Knee Arthroplasty, Sean Yueh

Master's Theses

The total knee arthroplasty (TKA) has become one of the most successful procedures in all of medicine, with an average of over 966,000 operations performed a year. Since its introduction in 1968, the TKA’s surgical process and implant designs have continuously been improved to increase survivability. However, the need for a revision TKA – due to aseptic loosening – continues to be a problematic aspect of the procedure. Stress shielding induced by different design parameters of the implant has generated controversy in the determination of an ideal configuration. The purpose of this study is to investigate how implant design parameters …

Simulation Of An Sp8t 18 Ghz Rf Switch Using Smt Pin Diodes, Andre De Souza Vigano

Master's Theses

Radio frequency (RF) and microwave switches are widely used in several different applications including radar, measurement systems, telecommunications, and other areas. An RF switch can control a radar’s transmit vs. receive mode, select the operating band, or direct an RF signal to different paths. In this study, a single pole eight throw (SP8T) switch using only Surface Mount (SMT) components is designed and simulated in Keysight’s Advanced Design System (ADS). Single pole eight throw is defined as one input and eight possible outputs. A star network configuration with series-shunt PIN diode switches is used to create the 8-way RF switch. …

Docs_On_Blocks – A Defense In Depth Strategy For E-Healthcare, Saad Mohammed

Electronic Theses, Projects, and Dissertations

With the increase in the data breaches and cyber hacks, organizations have come to realize that cyber security alone would not help as the attacks are becoming more sophisticated and complex than ever. E-Healthcare industry has shown a promising improvement in terms of security over the past, but the threat remains. Thus, the E-Healthcare industries are aiming towards a Defense in Depth Strategy approach.

The project here describes how a Defense in Depth Strategy for E-Healthcare system can provide an environment for better security of the data and peer-to-peer interaction with stakeholders. The legacy systems have at some point failed …

Coin Recovery Ii, Carly Lofthouse

Undergraduate Honors Capstone Projects

Western Metals Recycling (WMR), a subsidiary of NUCOR Steel, is a metals recycling company with a location in Plymouth, Utah. At Plymouth, a 50 NT/hr. non-ferrous recovery plant uses eddy current technology to generate a non-ferrous product called zorba. Zorba is a mix of aluminum, copper, brass, zinc, printed circuit boards, coins, lead, and the like. (Figure 1) The market value of zorba varies but generally ranges from $0.30 to $0.50 per pound. The value of the coins (not including pennies) is much higher than zorba price. The team's objective is to upgrade and optimize the existing trommel equipment to …

Real-Time Intelligent And Multi-Spectral Inspection Of Structural Components, Mst Mousumi Rizia

Open Access Theses & Dissertations

Conventional, manual inspection methods are the most commonly used inspection approaches to this day; that cause downtime and can be erroneous due to their repetitive nature, heavy workload, and human error. The overarching goal of this work is to advance structural inspection with intelligent and autonomous techniques across infrastructures. In particular, this project will develop path-planning schemes for close navigation around the structures and intelligent algorithms for crack and corrosion detection.

The introduced novel navigation method uses advanced manufacturing techniques to generate aerial inspection trajectories in GPS-denied areas. The proposed method is validated using the `Gazebo' robotics simulator; the results …

Recombinant Piriform Spider Silk Production, Cole R. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spider silks are remarkable biomaterials, possessing a variety of desirable mechanical and material properties. Humans have long-sought to utilize these materials. Spiders produce a range of different types of silks for different purposes, such as web-building, egg casing, and prey swathing. Because spiders are difficult to farm, a synthetic biological approach must be used to produce silk-like proteins. This research is intended to improve the production of piriform, a specific type of spider silk. This was done with targeted-improvements to microbial metabolism and recovery methodologies. The methods developed in this research are useful for other types of silk production and …

Effects Of Short Season Irrigation On Pasture Yield And Predicting Yield With Sentinel-2 Satellite, Ihsan Bugra Bugdayci

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Deficit irrigation can reduce agriculture water use making additional water available for other uses. This study looked at multi-year impacts of deficit irrigation on pasture yield. The results show that that early irrigation provides the most benefit to cool season pastures and late season irrigation only had small impacts on yield. According to this research, irrigation water can be saved without impacting the yield importantly.

Remote sensing techniques are becoming a part of agriculture. Yield predictions are important for the farmers and others involved with agriculture. In this research, relationships between the normalized difference vegetation index (NDVI) calculated from remotely …

Cost-Effective Planning Strategies For Battery Electric Bus Systems, Yi He

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent years, actions have been taken by countries around the world to create a more sustainable energy future. Electrifying transit buses is considered as a promising option to reduce emissions and increase sustainability of the transportation sector. However, there are still several barriers to the adoption of electric buses (e-buses). The barriers include, but are not limited to, the range limitations of e-buses, high up-front costs of e-buses, large capital expenses for charging infrastructure, and a lack of understanding regarding e-bus operation and management. This dissertation aims to overcome these barriers through the development of cost-effective planning strategies from …

Closed-Loop Propulsive Control For Very Low Perigee Orbit Energy Management And Stabilization, Tyler J. Gardner

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Within the past decade, the United States Air Force has begun exploring options for using smaller satellites, known as SmallSats and CubeSats, to decrease the time it takes to design and build new satellites. If used properly, a rapid development environment for satellites could improve the Air Force's ability to respond to new technologies and threats. Other organizations such as NASA and universities have been using SmallSats and CubeSats for research and development missions.

While smaller satellites are usually much cheaper to develop and require less time to create, limited volume strictly constrains the size of instrumentation and avionics that …