Engineering Commons^™

Development Of A Research Spacecraft Test-Bed With Implementation Of Control Laws To Compensate Undesired Dynamics, Yomary Angélica Betancur Vesga

Doctoral Dissertations and Master's Theses

The development of research spacecraft systems has a significant impact on the preparation and simulation of future space missions. Hardware, software and operation procedures can be adequately tested, validated and verified before they are deployed for the actual mission. In this thesis, a spacecraft vehicle test-bed named Extreme Access System (EASY) was developed. EASY aims at supporting validation and verification of guidance, navigation and control algorithms. Description of EASY spacecraft systems, sub-systems and integration is presented in this thesis along with an analysis of results from numerical simulation and actual implementation of control laws. An attitude control architecture based on …

Fuel Efficient Control Design And Constrained Motion Analysis For Spacecraft Coulomb Formation In Elliptic Chief Orbits, Muhammad Wasif Memon

Doctoral Dissertations and Master's Theses

The use of Coulomb force has been analyzed in recent years to provide propulsion in space for various applications. Coulomb formation can also be utilized to make close formation spacecraft missions fuel efficient. In this study, the Coulomb formation of two craft is studied in elliptic chief orbits for two formation geometries. The first formation requires both spacecraft to be aligned along the nadir (radial) direction and the second formation requires both spacecraft to maintain a constant separation distance relative to each other while each spacecraft rotates freely on the surface of a sphere with the ratio of the radii …

Numerical Investigation Of Scaling Effects Of A Ramjet-Powered Projectile, Arjun Jaishankar Vedam

Doctoral Dissertations and Master's Theses

Ramjet flowpath miniaturization is a potentially useful technology for integration into munitions to increase range, accuracy, and lethality. The emphasis of this effort is to numerically characterize the performance of a miniature hydrogen-fueled and ethylene-fueled ramjet flowpath during Mach 3 and Mach 3.5 sea-level flight. The effect of geometric scale on ramjet performance is evaluated using high-fidelity RANS CFD models. Sensitivity to nonequilibrium laminar and turbulence-limited chemistry, and transitional turbulence treatments are evaluated. The physical sources of small scale performance limitations are identified for both fuel types. Finally, flowpath integration for small-scale applications is briefly addressed.

In-Situ Measurement Of Resin Shrinkage For Aerospace Components, Samarth Motagi

Doctoral Dissertations and Master's Theses

Resin shrinkage due to chemical changes and thermal gradients plays an important role in the residual stress evolution during composite manufacturing. In this thesis, we develop a new in-situ experimental approach for measuring resin shrinkage during curing with the help of digital image correlation (DIC) instrumented on a specially designed autoclave with borosilicate viewports. The images of the resin sample are captured at regular intervals with the help of DIC to measure the displacement and strains during the curing process. We utilize this method for a comparative analysis of resin shrinkage in two common aerospace epoxies, Epoxy 105 and EPON …

Adaptive Learning Terrain Estimation For Unmanned Aerial Vehicle Applications, Pedro L. Vergara Garcia

Doctoral Dissertations and Master's Theses

For the past decade, terrain mapping research has focused on ground robots using occupancy grids and tree-like data structures, like Octomap and Quadtrees. Since flight vehicles have different constraints, ground-based terrain mapping research may not be directly applicable to the aerospace industry. To address this issue, Adaptive Learning Terrain Estimation algorithms have been developed with an aim towards aerospace applications. This thesis develops and tests Adaptive Learning Terrain Estimation algorithms using a custom test benchmark on representative aerospace cases: autonomous UAV landing and UAV flight through 3D urban environments. The fundamental objective of this thesis is to investigate the use …

Computational Model For Pedestrian Movement And Infectious Diseases Spread During Air Travel: A Molecular Dynamics-Like Numerical Approach, Pierrot Derjany

Doctoral Dissertations and Master's Theses

There is direct evidence of the transmission of fatal infectious pathogens in large human gatherings. Air transportation is no exception. The mixing of susceptible and infectious individuals in this high-density man-made environment involves pedestrian movement which is generally not taken into account in modeling studies of disease dynamics. This thesis addresses this problem through a multiscale model that combines pedestrian dynamics with stochastic infection spread models. This generic model is applicable to several directly transmitted diseases. Through this multiscale framework, the effectiveness of certain layout and strategies in suppressing the disease spread in highly crowded locations such as airplanes, airports …

A Step Toward Ending Long Airport Security Lines: The Modified Boarding Pass, Joel Lee

Doctoral Dissertations and Master's Theses

Anyone who has traveled by air has most likely experienced long airport security lines. Yet not much is known about its cause because few have considered if passengers have created this problem for themselves. The present study attempts to fill this research gap by suggesting that when passengers are not well-prepared for security screening, they delay the process by making mistakes and not complying with procedures. This lack of preparedness can be attributed to several shortcomings of security signposts. This study proposes the use of a modified boarding pass as an alternative form of signage to help passengers better prepare …

Astrodynamics Of The Next Generation Space Weather Prediction Mission, Mark Herring

Doctoral Dissertations and Master's Theses

Accurate prediction of the solar wind properties, interplanetary magnetic field direction and various space weather phenomena becomes ever more important as our dependence on Earth orbiting spacecraft increases. Different solar wind drivers can lead both to enhancements and losses of relativistic electrons in the outer radiation belts, thus posing a major risk to satellites. To further our understanding of the Sun’s impact on the near Earth space environment, as well as to provide predictive capabilities, a mission placing monitoring satellites in key orbits in the inner Solar System is being proposed. As part of that effort, the possibility of using …

Autonomous Autorotation Of A Tilt-Rotor Aircraft Using Model Predictive Control, Elias Wilson

Doctoral Dissertations and Master's Theses

Tilt rotor vehicles are governed by FAA laws also used for conventional helicopters, which require autorotational maneuvering and landing given a total power failure. With low inertia rotors and high disk loading of tilt rotor vehicles, this already difficult task becomes significantly more challenging. In this work, a model predictive controller is developed to autonomously maneuver and land a tilt rotor given complete power loss. A high fidelity model of a tilt rotor vehicle is created and used to simulate the vehicle dynamics and response to control inputs. A reduced order dynamic model is used within a model predictive control …

Comparison Of Indonesian Imports Forecastingby Limited Period Using Sarima Method, Harits Ar Rosyid, Mutyara Whening Aniendya, Heru Wahyu Herwanto

Knowledge Engineering and Data Science

The development of Indonesia's imports fluctuate over years. Inability to anticipate such rapid changes can cause economic slump due to inappropriate policy. For instance, recent years imports in rice led to the extermination of rice reserves. The reason is to maintain the market price of rice in Indonesia. To overcome these changes, forecasting the amount of imports should assist the Government in determining the optimum policy. This can be done by utilizing an algorithm to forecast time series data, in this case the amount of imports in the next few months with a high degree of accuracy. This study uses …

Mathematical Model, Simulated Design And Experimental Results For Parabolic Mirror Based Multiplexer For Spatially Multiplexed Fiber Optic Communication Systems, Ce Su

Theses and Dissertations

Spatial Domain Multiplexing (SDM) is a multi-input multi-output (MIMO) architecture. It adds an innovative dimension to optical fiber communication systems by enabling spatial reuse of the optical frequencies. SDM utilizes radially distributed spatial locations for different input signals based on their input launch angles. These input channels propagate in a helical path inside the carrier fiber. These SDM input channels do not encounter any perceptible cross-talk or inter-symbol interference. The SDM system is similar to other optical communication systems. However, they require two added parts. These parts are the spatial multiplexer, also known as the Beam Combiner Module (BCM) and …

Hvac System Energy Audit For Leverett Elementary School, Connor Smalling

Biological and Agricultural Engineering Undergraduate Honors Theses

Leverett Elementary School is located in Fayetteville, AR. The school needs significant upgrades to its infrastructure. The Fayetteville Public School District has voted to pursue an Energy Services Performance Contract (ESPC) in order to finance the desired upgrades to Leverett Elementary, among other schools in the district.

The scope of this thesis was to perform an energy audit on the existing heating, ventilation, and air conditioning (HVAC) system. By using an energy modeling software, eQuest, the building and the existing base system were modeled to determine utility consumption. Three different HVAC system alternatives were analyzed against the base system by …

Drivers Of On-Farm Performance Of Irrigation Water Management Practices: Empirical Evidence From Eastern Arkansas, Jacob Askey

Biological and Agricultural Engineering Undergraduate Honors Theses

Unsustainable agricultural practices are putting a strain on freshwater supplies in many parts of the world. More efficient irrigation techniques are going to be critical to feed a growing population. Data from the 2016 Arkansas Irrigation Survey was used to assess the adoption of three Irrigation Water Management (IWM) practices: multiple inlet rice irrigation, tailwater recovery, and storage reservoirs. Results indicate that these practices do not always lead to reported pumping time reductions, a proxy for water use savings. Large variations in pumping time reduction are observed across producers for all three practices. A Tobit model was used to examine …

Transmission-Scale Battery Energy Storage Systems: A Systematic Literature Review, Kevin Marnell, Manasseh Obi, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

When the transmission capacity of an electrical system is insufficient to adequately serve customer demand, the transmission system is said to be experiencing congestion. More transmission lines can be built to increase capacity. However, transmission congestion typically only occurs during periods of peak demand, which occur just a few times per year; capitol-intensive investments in new transmission capacity address problems that occur infrequently. Alternative solutions to alleviated transmission congestion have been devised, including generation curtailment, demand response programs, and various remedial action schema. Though not currently a common solution, battery energy storage systems can also provide transmission congestion relief. Technological …

Secure Two-Party Protocol For Privacy-Preserving Classification Via Differential Privacy, Manish Kumar

Boise State University Theses and Dissertations

Privacy-preserving distributed data mining is the study of mining on distributed data—owned by multiple data owners—in a non-secure environment, where the mining protocol does not reveal any sensitive information to the data owners, the individual privacy is preserved, and the output mining model is practically useful. In this thesis, we propose a secure two-party protocol for building a privacy-preserving decision tree classifier over distributed data using differential privacy. We utilize secure multiparty computation to ensure that the protocol is privacy-preserving. Our algorithm also utilizes parallel and sequential compositions, and applies distributed exponential mechanism to ensure that the output is differentially-private. …

Nanoscale Optical And Correlative Microscopies For Quantitative Characterization Of Dna Nanostructures, Christopher Michael Green

Boise State University Theses and Dissertations

Methods to engineer nanomaterials and devices with uniquely tailored properties are highly sought after in fields such as manufacturing, medicine, energy, and the environment. The macromolecule deoxyribonucleic acid (DNA) enables programmable self-assembly of nanostructures with near arbitrary shape and size and with unprecedented precision and accuracy. Additionally, DNA can be chemically modified to attach molecules and nanoparticles, providing a means to organize active materials into devices with unique or enhanced properties. One particularly powerful form of DNA-based self-assembly, DNA origami, provides robust structures with the potential for nanometer-scale resolution of addressable sites. DNA origami are assembled from one large DNA …

Axial Compressor Based On Plastic Additive Manufacturing, Chris Phu

Mechanical Engineering Undergraduate Honors Theses

Turbomolecular pumps designed to function in very low pressures tend to be too prohibitively expensive for student researchers. On the other hand, while conventional pumps are affordable, they can’t function in extreme low pressures. An additively manufactured axial compressor however is inexpensive to manufacturer and only needs to be build up enough pressure for a conventional pump to function. After many design iterations, a final iteration that is near vacuum chamber ready has been 3D printed and tested for spin functionally. The designed axial compressor is easy to assemble and very modular. Conclusions from each of the design iterations is …

Ultrasonic Wave Propagation In Copper/Graphene Metal Matrix Composites, Casey Lindbloom

Mechanical Engineering Undergraduate Honors Theses

Emerging metallic composite materials implanted with graphene sheets are showing immense promise, with benefits being observed with regards to mechanical, thermal, and electrical material properties. This research aims to investigate the effects on ultrasonic wave propagation in Copper/Graphene Metal Matrix Composites (Cu/Gr MMCs) with varying graphene arrangements inspired from nacre and bone nanoscale material distributions. To accomplish this, the molecular dynamics (MD) method is utilized to simulate nanoscale wave propagation on a set of Cu/Gr MMCs with differing graphene arrangements and volume percentages ranging up to 4.56%. The computational model results are then analyzed to determine the variation in energy …

Functional Importance Of Lipin Phosphorylation, Stephanie Elizabeth Hood

Graduate Theses and Dissertations

Highly conserved throughout evolution, lipins are dual functioning proteins found from yeast to humans. Functioning in the cytoplasm as phosphatidate phosphatase enzymes (PAP), lipins produce diacylglycerol that serves as a precursor for neutral fats and membrane phospholipids. Alternatively, nuclear lipins are responsible for the regulation of metabolic genes. Interestingly, both the mammalian lipin 1 paralog and the single Drosophila Lipin ortholog are highly phosphorylated proteins. Target of rapamycin (TOR) has previously been identified as one of the kinases that controls the subcellular localization of both lipin 1 and Drosophila Lipin. However, other serine and threonine kinases are predicted to be …

Improving Hydroshare And Web Application Interoperability Through Integrated Gis And His Data Services, Kenneth Jack Lippold

Theses and Dissertations

HydroShare is a collaborative online system being developed by the Consortium of Universities for the Advancement of Hydrologic Science Inc. (CUAHSI) with the goal of facilitating the dissemination, visualization, and publishing of hydrologic data and models. External web applications serve a key role in extending HydroShare's capabilities, so robust application programming interfaces (APIs) are a vital component of HydroShare's architecture. Hydrologic data stored on HydroShare are defined by a data type, and much of these data are either geospatial or time series data. Although HydroShare's API provides ways to upload and download files, as well as access certain metadata, it …

Investigation Of Electrocoating Mechanisms, Tyler James Marlar

Theses and Dissertations

The objective of this work is to advance the mechanistic understanding of cathodic electrocoating. These efforts are focused on the initial processes responsible for deposition, which are examined through direct experimentation and simulation. Electrocoating is a global industrial process providing a corrosive resistant base paint to automobile bodies. Presently, empirical models are used to model coating thickness; these models tend to overpredict deposition in occluded areas. Convection is implemented to study the behavior of adhered surface H2 bubbles on the substrate surfaces. The impact of surface H2 bubbles and early e-coat deposition on the local current density is studied using …

Variance Reduction In Wind Farm Layout Optimization, Bertelsen Gagakuma

Theses and Dissertations

As demand for wind power continues to grow, it is becoming increasingly important to minimize the risk, characterized by the variance, that is associated with long-term power forecasts. This thesis investigated variance reduction in power forecasts from wind farm layout optimization.The problem was formulated as a multi-objective optimization one of maximizing mean-plant-power and minimizing variance. The ε−constraint method was used to solve the bi-objectiveproblem in a two-step optimization framework where two sequential optimizations are performed. The first is maximizing mean wind farm power alone and the second, minimizing variance with a constraint on the mean power which is the value …

Trajectory Optimization And Design For A Large Number Of Unmanned Aerial Vehicles, Jenna Elisabeth Newcomb

Theses and Dissertations

An unmanned aerial vehicle (UAV) swarm allows for a more time-efficient method of searching a specified area than a single UAV or piloted plane. There are a variety of factors that affect how well an area is surveyed. We specifically analyzed the effect both vehicle properties and communication had on the swarm search performance. We used non-dimensionalization so the results can be applied to any domain size with any type of vehicle. We found that endurance was the most important factor. Vehicles with good endurance sensed approximately 90% to 100% of the grid, even when other properties were lacking. If …

Enabling Compact Devices Through Origami And Developable Mechanisms, Jacob Ryan Greenwood

Theses and Dissertations

This thesis provides resources that enable the design of novel and compact mechanical devices by providing terminology, engineering models, and design methods in the fields of developable mechanisms and origami-based engineering.The first part of this work presents engineering models to aid in the design of cylindrical developable mechanisms. These models take into account the added spatial restrictions imposed by the developable surface. Equations are provided for the kinematic analysis of cylindrical developable mechanisms. A new classification for developable mechanisms is also presented (intramobile, extramobile, and transmobile) and two graphical methods are provided for determining this classification for single-DOF planar cylindrical …

Characterization Of Local Void Content In Carbon Fiber Reinforced Plastic Parts Utilizing Observation Of In Situ Fluorescent Dye Within Epoxy, Wyatt Young Warner

Theses and Dissertations

Experimentation exploring the movement of voids within carbon fiber reinforced plastics was performed using fluorescent dye infused into the laminates observed through a transparent mold under ultraviolet light. In situ photography was used as an inspection method for void content during Resin Transfer Molding for these laminates. This in situ inspection method for determining the void content of composite laminates was compared to more common ex-situ quality inspection methods i.e. ultrasonic inspection and cross-section microscopy. Results for localized and total void count in each of these methods were directly compared to test samples and linear correlations between the three test …

Correction To: Better Beware: Comparing Metacognition For Phishing And Legitimate Emails (Metacognition And Learning, (2019), 14, 3, (343-362), 10.1007/S11409-019-09197-5), Casey I. Canfield, Baruch Fischhoff, Alex Davis

Engineering Management and Systems Engineering Faculty Research & Creative Works

The article "Better beware: comparing metacognition for phishing and legitimate emails", written by Casey Inez Canfield, Baruch Fischhoff and Alex Davis, was originally published electronically on the publisher's internet portal (currently SpringerLink) on 20 July 2019 without open access.

Mandela Splash Pad Pre-Construction Plan, Levi Sandbulte

Theses/Capstones/Creative Projects

In the construction industry, it is the responsibility of the general contractor to take the architect’s ideas and turn it into a real building. Many times this requires ample communication and several drafts. This efficient execution of this process is vital to the completion of a successful project. In this project, I practice this communication process. The challenge presented by the owner is to build an affordable splash pad, and without impacting the construction schedule of the Early Childhood Development Center (ECDC) that is being built on the same property at the same time. This proposal gives the owner a …

Waste Gasification, Glyn D. Lewis, Nash Taylor, Nicholas L. Ordonez, David S. Mccallum

Mechanical Engineering

This document summarizes the work the IGT Team has conducted on the topic of waste to energy gasification over the Cal Poly Winter, Spring, and Fall quarters of 2019. The project is being carried out by four Cal Poly Mechanical Engineering students: Nash Taylor, Glyn Lewis, David McCallum, and Nicholas Ordonez and the sponsor of this project is Tod duBois. The team’s original goal was to successfully create a system that compiles residential solid waste on a small scale, gasifies it, and measures the typical syngas outputs, so that the team may assess the viability of gasification of household waste …

Deployable Cover For Cubesat Fuv Imager, Edwin J. Rainville, Patrick J. Rainville, Jeff Wagner

Mechanical Engineering

The goal is to develop a deployable cover for a far ultraviolet imager cube satellite that will be used to map the earth’s auroras in the ionosphere. The deployable cover is used to protect the Far Ultra-Violet (FUV) sensor and lenses, house two mirrors which are used to filter unwanted light and expose optics when deployed. The deployable cover consists of a door, an actuator, a lockout mechanism, and an “open position” indicator. This project also includes designing a fixture for testing the optical alignment of the deployable cover after launch and during orbital conditions. The subassembly is required to …

Model Block Press Design, Ben Todd Van Hamersveld, Chester Wong, Alexander Wing-Jon Giannousis

Mechanical Engineering

This project’s goal is to redesign the Center for Vocational Building Technology (CVBT) BP9 earth block press, which makes 1/3 scale compressed earth blocks to build demonstration model homes in Thailand. The full-scale block press, the BP6, provides a sustainable and affordable technique for constructing habitable homes in Thailand. The BP9 serves as a tool to inform the public of the advantages of human-powered earth block presses through demonstration. The BP9 press design has multiple problems: it is too expensive to manufacture, there is too much friction when used, it has several weak points due to users unintentionally applying excessive …