Digital Commons Network^™

Utilizing Permanent On-Board Water Storage For Efficient Deep Space Radiation Shielding, Nathan Ryan Gehrke

Master's Theses

As space technologies continue to develop rapidly, there is a common desire to launch astronauts beyond the ISS to return to the Moon and put human footsteps on Mars. One of the largest hurdles that still needs to be addressed is the protection of astronauts from the radiation environment seen in deep space. The most effective way to defend against radiation is increasing the thickness of the shield, however this is limited by strict mass requirements. In order to increase the thickness of the shield, it is beneficial to make mission critical items double as shielding material.

The human rated …

Exploring The Concept Of A Deep Space Solar-Powered Small Spacecraft, Kian Guillaume Crowley

Master's Theses

New Horizons, Voyager 1 & 2, and Pioneer 10 & 11 are the only spacecraft to ever venture past Pluto and provide information about space at those large distances. These spacecraft were very expensive and primarily designed to study planets during gravitational assist maneuvers. They were not designed to explore space past Pluto and their study of this environment is at best a secondary mission. These spacecraft rely on radioisotope thermoelectric generators (RTGs) to provide power, an expensive yet necessary approach to generating sufficient power. With Cubesats graduating to interplanetary capabilities, such as the Mars-bound MarCO spacecraft, matching the modest …

Use Of Manifolds In The Insertion Of Ballistic Cycler Trajectories, Oliver K. Morrison

Master's Theses

Today, Mars is one of the most interesting and important destinations for humankind and copious methods have been proposed to accomplish these future missions. One of the more fascinating methods is the Earth-Mars cycler trajectory which is a trajectory that accomplishes repeat access to Earth and Mars with little to no fuel-burning maneuvers. This would allow fast travel to and from Mars, as well as grant the possibility of multiple missions using the same main vehicle.

Insertion from Earth-orbit onto the cycler trajectory has not been thoroughly ex- plored and the only existing method so far is a Hohmann-esque transfer …

Improving Introductory Computer Science Education With Draco, Mike Dongyub Ryu

Master's Theses

Today, many introductory computer science courses rely heavily on a specific programming language to convey fundamental programming concepts. For beginning students, the cognitive capacity required to operate with the syntactic forms of this language may overwhelm their ability to formulate a solution to a program.

We recognize that the introductory computer science courses can be more effective if they convey fundamental concepts without requiring the students to focus on the syntax of a programming language. To achieve this, we propose a new teaching method based on the Design Recipe and Code Outlining (DRaCO) processes. Our new pedagogy capitalizes on the …

Dynamics Simulation And Optimal Control Of A Multiple-Input And Multiple-Output Balancing Cube, Felix K. Haimerl

Master's Theses

This thesis document outlines the development of a multibody dynamics simulation of an actively stabilized multiple-input, multiple-output, coupled, balancing cube and the process of verifying the results by implementing the control algorithm in hardware. A non-linear simulation of the system was created in Simscape and used to develop a Linear Quadratic Gaussian control algorithm. To implement this algorithm in actual hardware, the system was first designed, manufactured, and assembled. The structure of the cube and the reaction wheels were milled from aluminum. DC brushless motors were installed into the mechanical system. In terms of electronics, a processor, orientation sensor, motor …

Optimizing The Distributed Hydrology Soil Vegetation Model For Uncertainty Assessment With Serial, Multicore And Distributed Accelerations, Andrew Adriance

Master's Theses

Hydrology is the study of water. Hydrology tracks various attributes of water such as its quality and movement. As a tool Hydrology allows researchers to investigate topics such as the impacts of wildfires, logging, and commercial development. With perfect and complete data collection researchers could answer these questions with complete certainty. However, due to cost and potential sources of error this is impractical. As such researchers rely on simulations.

The Distributed Hydrology Soil Vegetation Model(also referenced to as DHSVM) is a scientific mathematical model to numerically represent watersheds. Hydrology, as with all fields, continues to produce large amounts of data …

Protection, Automation, And Frequency Stability Analysis Of A Laboratory Microgrid System, Christopher Eric Osborn

Master's Theses

Due to increasing changes in the power industry, Cal Poly San Luis Obispo's electrical engineering department introduced a set of initiatives to adequately equip students with the skills and knowledge to interact with new technologies. Specifically, the department proposed a microgrid and power systems protection and automation laboratory to strengthen students' knowledge of microprocessor-based relays. This paper outlines a microgrid laboratory system that fulfills the initiative's goal and proposes a collection of laboratory experiments for inclusion in a new laboratory course at Cal Poly. The experiments provide students with practical experience using Schweitzer Engineering Laboratory (SEL) relays and teach fundamental …

Analysis Of Verification And Validation Techniques For Educational Cubesat Programs, Noah Weitz

Master's Theses

Since their creation, CubeSats have become a valuable educational tool for university science and engineering programs. Unfortunately, while aerospace companies invest resources to develop verification and validation methodologies based on larger-scale aerospace projects, university programs tend to focus resources on spacecraft development. This paper looks at two different types of methodologies in an attempt to improve CubeSat reliability: generating software requirements and utilizing system and software architecture modeling. Both the Consortium Requirements Engineering (CoRE) method for software requirements and the Monterey Phoenix modeling language for architecture modeling were tested for usability in the context of PolySat, Cal Poly's CubeSat research …

Protection Against Ungrounded Single Phase Open Circuit Faults In 3-Phase Distribution Transformers, Higinio Ariel Montoya

Master's Theses

This thesis explores the impacts and behavior of 3-phase distribution transformers when subject to ungrounded single phase open circuit faults. A simple 3-phase system is modeled using MATLAB Simulink and operation under fault conditions are simulated and studied. Simulation results are confirmed via lab experimentation. Finally, a robust detection and protection method using neutral current injection (as proposed in industry literature) is built and demonstrated.

Electric utility operating experience has demonstrated that all too often, loads on 3-phase distribution transformers are not adequately protected against an ungrounded single phase open circuit fault (commonly called “single phasing”). This type of fault …

Knee Angles And Axes Crosstalk Correction In Gait, Cycling, And Elliptical Training Exercises, Jordan M. Skaro

Master's Theses

When conducting motion analysis using 3-dimensional motion capture technology, errors in marker placement on the knee results in a widely observed phenomenon known as “crosstalk” [1-18] in calculated knee joint angles (i.e., flexion-extension (FE), adduction-abduction (AA), internal-external rotation (IE)). Principal Component Analysis (PCA) has recently been proposed as a post hoc method to reduce crosstalk errors and operates by minimizing the correlation between the knee angles [1, 2]. However, recent studies that have used PCA have neither considered exercises, such as cycling (C) and elliptical training (E), other than gait (G) nor estimated the corrected knee axes following PCA correction. …

Computational Validation Of Aerodynamic Paramenters On A Multi-Sided Cylinder, Christopher Ong

Master's Theses

There are fundamental problems in fluid dynamics. One common problem is fluid flow around cylinder-shaped bodies which range from circular to multi-sided polygons. These basic geometric shapes are found in various applications. With the increased availability of computational power, the use of Computational Fluid Dynamics (CFD) becomes an avenue for studying fluid flow around theses shapes. The fluid flow over cylindrical bodies is a widely studied problem used to validate the accuracy and reliability of CFD codes before working on more complex engineering problems. This validation is done by comparing selected flow parameters to experimental results to determine the accuracy …

Sysml Output Interface And System-Level Requirement Analyzer For The Horizon Simulation Framework, Viren Kishor Patel

Master's Theses

Model-Based Systems Engineering in industry has been constantly increasing its presence within the aerospace industry. SysML is one such MBSE tool that shows complex system organization and relationships. The Horizon Simulation Framework is another MBSE tool, created by Cal Poly students, that gives users the ability to run “day-in-the-life” simulations of systems. Finding a way to link these two tools could allow systems engineers to reap the benefits of both.

This thesis investigates the background and design process involved with developing the code that can convert an output file generated in SysML, into a format specifically made for the Horizon …

Rotordynamic Analysis Of Theoretical Models And Experimental Systems, Cameron R. Naugle

Master's Theses

This thesis is intended to provide fundamental information for the construction and

analysis of rotordynamic theoretical models, and their comparison the experimental

systems. Finite Element Method (FEM) is used to construct models using Timoshenko

beam elements with viscous and hysteretic internal damping. Eigenvalues

and eigenvectors of state space equations are used to perform stability analysis, produce

critical speed maps, and visualize mode shapes. Frequency domain analysis

of theoretical models is used to provide Bode diagrams and in experimental data

full spectrum cascade plots. Experimental and theoretical model analyses are used

to optimize the control algorithm for an Active Magnetic Bearing …

Modeling And Analysis Of Cal Poly Microgrid, Matthew A. Guevara

Master's Theses

Microgrids—miniature versions of the electrical grid are becoming increasingly more popular as advancements in technologies, renewable energy mandates, and decreased costs drive communities to adopt them. The modern microgrid has capabilities of generating, distributing, and regulating the flow of electricity, capable of operating in both grid-connected and islanded (disconnected) conditions. This paper utilizes ETAP software in the analysis, simulation, and development of the Cal Poly microgrid. Additionally, an ETAP power system protection tutorial is created to aid students entering the power industry. Microprocessor-based relays are heavily utilized in both the ETAP model and hardware implementation of the system. Case studies …

Modeling Adversarial Insider Vehicles In Mix Zones, Nicholas Plewtong

Master's Theses

Security is a necessity when dealing with new forms of technology that may not have been analyzed from a security perspective. One of the latest growing technological advances are Vehicular Ad-Hoc Networks (VANETs). VANETs allow vehicles to communicate information to each other wirelessly which allows for an increase in safety and efficiency for vehicles. However, with this new type of computerized system comes the need to maintain security on top of it.

In order to try to protect location privacy of the vehicles in the system, vehicles change pseudonyms or identifiers at areas known as mix zones. This thesis implements …

Predicting The Vote Using Legislative Speech, Aditya Budhwar

Master's Theses

As most dedicated observers of voting bodies like the U.S. Supreme Court can attest, it is possible to guess vote outcomes based on statements made during deliberations or questioning by the voting members. In most forms of representative democracy, citizens can actively petition or lobby their representatives, and that often means understanding their intentions to vote for or against an issue of interest. In some U.S. state legislators, professional lobby groups and dedicated press members are highly informed and engaged, but the process is basically closed to ordinary citizens because they do not have enough background and familiarity with the …

Applying Neural Networks For Tire Pressure Monitoring Systems, Alex Kost

Master's Theses

A proof-of-concept indirect tire-pressure monitoring system is developed using neural net- works to identify the tire pressure of a vehicle tire. A quarter-car model was developed with Matlab and Simulink to generate simulated accelerometer output data. Simulation data are used to train and evaluate a recurrent neural network with long short-term memory blocks (RNN-LSTM) and a convolutional neural network (CNN) developed in Python with Tensorflow. Bayesian Optimization via SigOpt was used to optimize training and model parameters. The predictive accuracy and training speed of the two models with various parameters are compared. Finally, future work and improvements are discussed.

Powder Bed Surface Quality And Particle Size Distribution For Metal Additive Manufacturing And Comparison With Discrete Element Model, Irene Yee

Master's Theses

Metal additive manufacturing (AM) can produce complex parts that were once considered impossible or too costly to fabricate using conventional machining techniques, making AM machines an exceptional tool for rapid prototyping, one-off parts, and labor-intensive geometries. Due to the growing popularity of this technology, especially in the defense and medical industries, more researchers are looking into the physics and mechanics behind the AM process. Many factors and parameters contribute to the overall quality of a part, one of them being the powder bed itself. So far, little investigation has been dedicated to the behavior of the powder in the powder …

Manufacture Of Complex Geometry Component For Advanced Material Stiffness, David Russell Bydalek

Master's Theses

The manufacture, laminate design, and modeling of a part with complex geometry are explored. The ultimate goal of the research is to produce a model that accurately predicts part stiffness. This is validated with experimental results of composite parts, which refine material properties for use in a final prototype part model. The secondary goal of this project is to explore manufacturing methods for improved manufacturability of the complex part. The manufacturing portion of the thesis and feedback into material model has incorporated a senior project team to perform research on manufacturing and create composite part to be used for experimental …

Single Camera Photogrammetry Matlab Solver Developed For Automation Of The Oil Interferometry Process, Hunter Michael Dunn

Master's Theses

Over the last 20 years, Gregory G. Zilliac of the NASA AMES Research Center has been in continuous development of a fringe-imaging skin friction PC application used in oil interferometry analysis. This application, CXWIN5G, allows users to analyze propagation of oil smears across an aerodynamic surface using photogrammetry. The purpose of this thesis is to investigate the feasibility of increasing the level of automation currently found in CXWIN5G by developing a MATLAB solver capable of determining oil smear geometry with minimal user input.

There are two main automation goals of this thesis that are reflected in the core of the …