Digital Commons Network^™

Spacecraft Trajectory Optimization Suite: Fly-Bys With Impulsive Thrust Engines (Stops-Flite), Aaron H. Li

Master's Theses

Spacecraft trajectory optimization is a near-infinite problem space with a wide variety of models and optimizers. As trajectory complexity increases, so too must the capabilities of modern optimizers. Common objective cost functions for these optimizers include the propellant utilized by the spacecraft and the time the spacecraft spends in flight. One effective method of minimizing these costs is the utilization of one or multiple gravity assists. Due to the phenomenon known as the Oberth effect, fuel burned at a high velocity results in a larger change in orbital energy than fuel burned at a low velocity. Since a spacecraft is …

System Identification Of A Cantilever Beam With Interferometer Measurement Using Adaptive Filters, Jordan D. Kochavi

Master's Theses

Laser interferometry, commonly used in high-precision motion control systems, is rarely adopted in experimental vibration analysis because its installation and mounting is invasive to dynamical systems. However, metrology systems that already utilize laser interferometry, such as profilometry in semiconductor manufacturing, may benefit from interferometer feedback for signal processing. This study investigates the use of laser interferometry for system identification through a piezoelectrically actuated cantilevered beam.

The model of the beam including piezo actuators and optical measurement components are established through the Euler-Bernoulli beam theory. From the method of separation of variables, the continuous system is transformed into a discrete system …

Rasm: Compiling Racket To Webassembly, Grant Matejka

Master's Theses

WebAssembly is an instruction set designed for a stack based virtual machine, with an emphasis on speed, portability and security. As the use cases for WebAssembly grow, so does the desire to target WebAssembly in compilation. In this thesis we present Rasm, a Racket to WebAssembly compiler that compiles a select subset of the top forms of the Racket programming language to WebAssembly. We also present our early findings in our work towards adding a WebAssembly backend to the Chez Scheme compiler that is the backend of Racket. We address initial concerns and roadblocks in adopting a WebAssembly backend and …

The Effects Of Atomic Oxygen On Silicone And Carbon-Based Contamination, Mayana W. Gordon

Master's Theses

Understanding the space environment and contamination concerns of a spacecraft is critical in designing a successful mission. The ability for a spacecraft to meet its science objectives relies on systems functioning as intended. A concern for maintain- ing performance while on orbit is molecular contamination. Silicones have previously been shown to form a silica layer on their surfaces when exposed to atomic oxygen. For silicone contamination, this translates to a silica film on the contaminated surface. Missions such as Long Duration Exposure Facility and Evaluation of Oxygen Interactions with Materials III have indicated that the silica film can trap deposits …

Exploring The Numerical Range Of Block Toeplitz Operators, Brooke Randell

Master's Theses

We will explore the numerical range of the block Toeplitz operator with symbol function \(\phi(z)=A_0+zA_1\), where \(A_0, A_1 \in M_2(\mathbb{C})\). A full characterization of the numerical range of this operator proves to be quite difficult and so we will focus on characterizing the boundary of the related set, \(\{W(A_0+zA_1) : z \in \partial \mathbb{D}\}\), in a specific case. We will use the theory of envelopes to explore what the boundary looks like and we will use geometric arguments to explore the number of flat portions on the boundary. We will then make a conjecture as to the number of flat …

Design Justice In Community-Oriented Engineering Pedagogy And Practice, Michael S. Reyna

Master's Theses

While engineering service-learning projects are seen as a favorable way for students to reinforce curricular learning while gaining cultural awareness, the outcomes of these projects center student benefits over partner community wellbeing. For these projects, and in other engineering contexts, various scholar-activists have conceptualized numerous principles and methods to center justice and equity in engineering outcomes. This research project and its associated intervention involved collecting scholarship and methods in engineering and social justice, and attempted to integrate these ideas into the practices of a local humanitarian service-learning engineering team. The collected scholarship centered around the topics of Design Justice, feminist …

A Nano-Drone Safety Architecture, Connor J. Sexton

Master's Theses

As small-form factor drones grow more intelligent, they increasingly require more sophisticated capabilities to record sensor data and system state, ensuring safe and improved operation. Already regulations for black boxes, electronic data recorders (EDRs), for determining liabilities and improving the safety of large-form factor autonomous vehicles are becoming established. Conventional techniques use hardened memory storage units that conserve all sensor (visual) and system operational state; and N-way redundant models for detecting uncertainty in system operation. For small-form factor drones, which are highly limited by weight, power, and computational resources, these techniques become increasingly prohibitive. In this paper, we propose a …

Ofdm Channel Estimation With Artificial Neural Networks, Joseph W. Bednar

Master's Theses

The use of orthogonal frequency-division multiplexing (OFDM) by wireless standards is often preferred due to its high spectral efficiency and ease of implementation. However, data transmission via OFDM still suffers when passing through a noisy channel. In order to maximize the abilities of OFDM, channel effects must be corrected. Unfortunately, channel estimation is often difficult due to the nonlinearity and randomness present in a practical communication channel.

Recently, machine learning based approaches have been used to improve existing channel estimation algorithms for a more efficient transmission. This thesis investigates the application of artificial neural networks (ANNs) as a means of …

On The Numerical Range Of Compact Operators, Montserrat Dabkowski

Master's Theses

One of the many characterizations of compact operators is as linear operators which
can be closely approximated by bounded finite rank operators (theorem 25). It is
well known that the numerical range of a bounded operator on a finite dimensional
Hilbert space is closed (theorem 54). In this thesis we explore how close to being
closed the numerical range of a compact operator is (theorem 56). We also describe
how limited the difference between the closure and the numerical range of a compact
operator can be (theorem 58). To aid in our exploration of the numerical range of
a compact …

Design And Analysis Of N-Path Filter For Radio Frequencies, Nathan M. Bergen

Master's Theses

Due to the growth of wireless communication many communication frequencies have grown increasingly dense. This density requires higher Q-factor to receive only the signal of interest. With the rise of smaller integrated circuits previous solutions used for filtering have become viable again. This paper explores whether the N-path filter is viable in the modern day for radio frequency receiver purposes. A non-differential N-path filter was created by utilizing Cadence Virtuoso with a working center frequency range of 750MHz to 1GHz while using TSMC technology. The desired quality factor of over 1,000 was reached while maintaining a total area of 800 …

Measuring Accessibility For Pedestrians, Bicyclists, And Transit Riders To Grocery Stores In The Excelsior/Outer Mission Neighborhoods Of San Francisco, Alexandra Lee-Gardner

Master's Theses

Grocery stores are an important amenity in neighborhoods and access to grocery stores is important for health and well-being. While grocery store accessibility is a popular topic of research, studies measuring access for pedestrians, bicyclists, and transit riders are extremely rare. When a new store opened in the Excelsior/Outer Mission districts of San Francisco on a street lacking basic infrastructure for pedestrians, bicyclists, and transit riders, the importance of this study became apparent. The Excelsior/Outer Mission neighborhood has a shocking number of collisions (over 1,100 between 2015 and 2019), elevated levels of walking, biking, and transit ridership, and minimal safe …

Modeling And Control Of A Planar Bounding Quadrupedal Robot, Patrick John Ward

Master's Theses

Legged robots have the potential to be a valuable technology that provides agile and adaptive locomotion over complex terrain. To realize legged locomotion's full abilities a control design must consider the nonlinear piecewise dynamics of the systems. This paper aims to develop a controller for the planar bounding of a quadrupedal robot.

The bounding of the quadruped robot is characterized by a simplified hybrid model that consists of two subsystems for stance and flight phases and the switching laws between the two states. An additional model, the Multibody model, with fewer simplifications, is used concurrently to best approximate real-world behavior. …

The Effects Of Cofermentation Of Cider And Apple Pomace On Cider Attributes, Abigail D. Affonso

Master's Theses

Phenolics are critical to the sensory attributes and health benefits of hard cider due to their contribution to the flavor, mouthfeel, and antioxidant activity. With the increase in demand for cider, the use of dessert apple varieties has become more common leaving ciders lacking in phenolics. However, a promising method to increase their phenolic content is through maceration with apple pomace. This study evaluated the effect maceration with apple pomace during cider fermentation on the extraction of phenolic compounds, as well as its effect on the sensory properties of the final product. For this study, ciders were fermented with 0% …

Design Of A Proprioceptive Actuator Utilizing A Cycloidal Gearbox, Craig John Kimball

Master's Theses

Legged robotics creates the demand for high torque compact actuators able to develop high instantaneous torque. Proprioceptive actuator design theory is a design theory that removes the need for a torque feedback device and relies on the stiffness in the leg for absorbing the high Ground Impact Forces created by walking locomotion. It utilizes a high torque density motor paired with a gearbox with a high gear ratio for torque multiplication. Previously work has been done to design a proprioceptive actuator design that utilizes a planetary gearbox to create a modular low-cost actuator for legged robotics. The purpose of this …

Feasibility Report On Water Recycling And The Housing Crisis, Tally A. Perry

City and Regional Planning

The western United States is experiencing increasing population, a housing shortage, and a drought. These challenges demand creative and unprecedented changes to development. Water recycling is slowly emerging as a viable solution for developers, home owners, and cities as a way to continue much-needed housing development while mitigating unnecessary water depletion. With all change, policy, feasibility, and awareness can be the largest influencers. Drought-ridden western-American states require additional and revised regulatory requirements to promote recycled water in new development. Currently, water reuse is largely used for agricultural and industrial purposes. To motivate and encourage housing development, water recycling needs to …

Proposed Traffic Calming Measures Along S La Tijera Boulevard, Ariella Stanford

City and Regional Planning

This document presents the context and design process for multiple traffic calming measures along S La Tijera Boulevard in Los Angeles, CA. The following chapters outline an assessment of the site and surrounding area, analyzation of case studies that are similar to the proposed project, the vision of the project, and the design of the proposal.

Legislative Language For Success, Sanjana Gundala

Master's Theses

Legislative committee meetings are an integral part of the lawmaking process for local and state bills. The testimony presented during these meetings is a large factor in the outcome of the proposed bill. This research uses Natural Language Processing and Machine Learning techniques to analyze testimonies from California Legislative committee meetings from 2015-2016 in order to identify what aspects of a testimony makes it successful. A testimony is considered successful if the alignment of the testimony matches the bill outcome (alignment is "For" and the bill passes or alignment is "Against" and the bill fails). The process of finding what …

Exploring The Post-Funicular At Cal Poly, Spencer Bazer, Kieran Mccullough

Architectural Engineering

In this studio we investigated the design and construction of a shell structure through form finding, form testing, and form making. By using a physics-based approach through Kangaroo on Grasshopper, we were able to create a form that minimized tension in the shell. Once a form was found, testing followed through full-scale construction. An iterative process between architectural engineering students and architecture students helped to create a realistic and elegant design.

Smart Usb-C Wall Plug For The Dc House Project, Ridge Lahti, Dino Maslic

Electrical Engineering

DC operated devices and appliances powered by AC systems suffer inefficiencies resulting from the losses of converting AC energy into DC energy. At Cal Poly, the DC House Project aims to minimize the need for AC electricity in homes and encourage the use of renewable energy systems. The DC House uses a 48V DC bus that must be stepped down for use with increasing number of DC loads in a typical home. In this project, a Smart USB-C Wall Plug is designed to work with USB Power Delivery to provide a variable voltage output for use with these DC loads …

Current-Source Dc-Dc Converter, Rocio Sanchez-Mendoza, Carlos Aguilar, Adrian Aranjo

Electrical Engineering

In this project, a hardware implementation of a current-source DC-DC converter for powering sensors used in an underwater communications system is presented. The proposed converter is designed to step down an input current of 0.9 A to 0.625 A, while maintaining an output voltage of 24 V and output power of 15 W. An overview of the system design is explained as well as the component selection process. The design of the converter was simulated and evaluated using LTspice before being physically constructed on a printed circuit board. Performance evaluation of the proposed converter was carried out in multiple lab …

Hvac Hardware Modeling Using Programmable Automatic Controller, Panthil Ketan Patel, Lumanti Tuladhar

Electrical Engineering

The primary purpose of this project is to use the donated programmable logic controllers (PLC) from Schneider Electric to develop experiments for a future lab class at Cal Poly. Our goal as the first group working on this project is to develop an experiment where the PLC can control the HVAC system based on temperature and humidity sensors and user inputs to maintain a desired consistent temperature. The PLC will be controlled using Unity Pro XLS/Control Expert software for simulations. The overall purpose of the experiments will be to demonstrate the potential of the PLC to minimize manual intervention while …

Standalone Wireless Humming Music Synthesizer, Elizaveta Viktorovna Koush, Conrad Kinsey, Alberto Munoz

Electrical Engineering

This project, called a standalone wireless humming music synthesizer, aimed to provide a tool for musicians to make creating music easier. It did this by removing learning barriers and adding an assistive functionality element that current synthesizers fail to address.

Existing methods for synthesizers typically include a keyboard or some collection of buttons to play melodies on. This requires the knowledge of music theory and a learning curve for the instrument, and this device aims to tackle this barrier. A device that can synthesize your voice into high-quality audio removes this musical knowledge barrier and allows anyone to easily convert …

Mars Rover Structure, Ethan Nikcevich, Justin Marhoefer, Will Kish, Brenden Billing

Mechanical Engineering

Our project is the third iteration of a design to create a small Mars rover. Our main challenge was to change the existing rover structure into something that could survive the harsh conditions of Mars. This meant altering the design so that it could resist the large temperature fluctuations while still maintaining the structural stability and interface to support driving functions and the projects of the other rover teams. Our team accomplished this goal by altering the design of the existing rocker bogey from completely 3D printed to a tube and joint system. The longer portions of the rocker bogey …

Burt's Bees: Branding And Packaging Update, Mia Rogers

Graphic Communication

This project will focus on examining the existing brand identity, package design, and social media marketing collateral for Burt’s Bees personal care company in order to create updated versions of each. I will be re-branding the products to appeal to a wider target audience, focusing primarily on Generation Z and their consumer preferences.

My deliverables will consist of a complete brand style guide (logo variations, primary and secondary color palettes, typography, and visual collateral), updated packaging (four popular lip balm flavors, the beeswax hand salve, and two facial cleansers), and an example of a digital advertisement showcasing the new brand …

Montagna Restaurant Brand And Website Development, Kevin A. Shin-Wheeler

Graphic Communication

My goal for this project was to provide engaging branding and collateral for the fictitious Montagna restaurant to increase its consistency and tangibility. I wanted to create a design guideline for all aspects of the Montagna brand to ensure that Montagna’s logo, typefaces, colors, interaction elements, and other stylistic choices are aesthetically pleasing and match the brand’s identity. Next, set out to make an accessible, interactive, and exciting website for the restaurant and a cohesive menu aligning with the design specifications. Although the brand is fictitious, I wanted to design it with actual needs in mind so that somebody could …

Codes Of Conduct In Student Media: An Analysis Of Student Perceptions Of Ethics Codes, Torstein A. Rehn

Journalism

The following is a study into students' perceptions of codes of conduct in student media organizations. Codes of conduct in a media setting have long been a focus of research, but little research has been done into their application in a student media environment. Student media organizations operate in a unique setting where they are entirely staffed by novice reporters. These organizations double as training grounds for students and as legitimate news sources. This study seeks to analyze this phenomenon by interviewing student media members. The goal of this study is to understand what current students seek in a code …

A Comparison Of Exotic And Pyraf In Analyzing Exoplanet Transits, Kailei A. Gallup

Physics

In this paper we discuss the data analysis processes using PyRaf, a Python-based version of IRAF, which is one of the most commonly used coding softwares in the astronomy community, as well as the analysis process using EXOTIC. Additionally, we will compare the outcomes from each process to determine if either has significant benefits over the other.

Developing A Data Acquisition System For Use In Cold Neutral Atom Traps, Jonathan E. Fuzaro Alencar

Physics

The rising interest in quantum computing has led to new quantum systems being developed and researched. Among these are trapped neutral atoms which have several desirable features and may be configured and operated on using lasers in an optical lattice. This work describes the development of a new data acquisition system for use in tuning lasers near the precise hyperfine transition frequencies of Rb 87 atoms, a crucial step in the functionality of a neutral atom trap. This improves on previous implementations that were deprecated and limited in laser frequency sweep range. Integration into the experiment was accomplished using an …

A Comparative Study Of The Effects Of Microalgae On Poultry Production, Taylor Kaitlyn O'Lear Reid

Master's Theses

Research has shown Spirulina to be a viable feedstuff in poultry production. Other species of microalgae are being studied to determine their effects on poultry production. This project compared four microalgaes: Hydrodictyon, Vaucheria, Uronema, and Spirulina and was broken down into three trials. The first experiment investigated the digestibility of an algae species, Spirulina, in broiler chicken diets. Eighty, 25-day-old Ross 708 broiler chicks were sorted into 20 metabolism cages and received one of two diets: Control Diet or Test Diet (75% basal diet + 25% Spirulina). The apparent ileal amino acid digestibility (AIAAD) of lysine, methionine, cysteine, threonine, isoleucine, …

Self-Balancing Bicycle Device, Charles Cole, Raffy Lorenzo, Neil Boyal

Biomedical Engineering

The sponsor, Justin Shaw, is currently developing a bicycle for an athlete who has lost movement in their legs. This athlete can no longer experience the unmatched feeling of naturally banking a bicycle at corners. The Self-Balancing Bike Device Team will create a device that can self-balance an electric recumbent bicycle at low speeds while being almost undetectable while turning. This document will outline the team’s background research into self-balancing vehicles, define the needs that must be solved, and delineate a schedule for future milestones.