Aerospace Engineering Commons^™

Accelerated Aging Of Adhesively Bonded Composite Joints For Use In Material Screening And Selection During Development: A Review And Case Study, Marie Danielle Flanigan

Theses and Dissertations

Adhesively bonded structures are used in many high-tech industries such as aerospace, automotive, and defense. The application of these joints using composite adherends has increased in recent years because of improved strength-to-weight ratio, design flexibility, and lower concern for corrosion. Quality acceptance of these structures largely depends on reliability and durability which includes influence of environmental service conditions on long-term behavior. Characterization of long-term behavior presents a difficult challenge to those involved in material selection and design due to the long service life of the joint compared to the development time available and complexity of the degradation mechanisms. Therefore, different …

Project Management And Systems Engineering Framework For Educational Cubesat Missions, Bailey Garrett

Master's Theses

The rising complexity of CubeSat missions and the unique challenges faced by educational CubeSat programs lead to high rates of mission failure. Implementing project management and systems engineering practices can alleviate these challenges and improve mission success rates for educational CubeSat developers. However, existing project management and systems engineering resources are too cumbersome and often assume the student has a base-level understanding of project management and systems engineering fundamentals. A new universal project management and systems engineering framework was created and tailored specifically to the needs of an educational CubeSat mission. The framework was designed to accommodate first-time CubeSat developers, …

Effects Of Atomic Oxygen On Outgassing Of Silicone Materials, Samuel Westrick

Master's Theses

An important consideration for spacecraft material selection is the space environment that the spacecraft will be operating in. Two features of the space environment that drive material selection are material outgassing and the presence of atomic oxygen in low Earth orbit (LEO). Materials that are considered for use in space are tested to be able to understand how they’ll outgas on orbit and how they’ll respond to interactions with atomic oxygen. However, testing to understand how atomic oxygen interaction with a material will affect how the material will outgas is rare and not standardized. This thesis used a vacuum chamber …

A Mechanically Intelligent Hosing-Drone, Blake Hament

UNLV Theses, Dissertations, Professional Papers, and Capstones

This manuscript presents a ”mechanically intelligent” approach to designing a Hosing-Drone for heavy-duty pressure washing. Spraying a hose creates strong reaction forces and torques. Previously demonstrated spraying robots are over-engineered to be very massive with huge inertias. These high inertias ”wash out” the reaction from the spraying. In the proposed approach, the contributions from all observable fluid dynamics, fluid structure interactions, and aerodynamics are studied individually and for the coupled system. Experimental data is collected and fit to dynamic models. These models are used to design a smaller, lighter, more agile vehicle than has been previously demonstrated. An impedance controller …

Analysis Of Propeller Designs Focusing On Lowering Sound Pressure Level Through Reduced Tip Loading, Luca A. Zeitvogel

Theses and Dissertations

This research focused on potential design optimizations for small propellers. Designs sought to reduce noise generated without sacrificing efficiency by “unloading” the propeller tip by reducing angle of attack near the tip. To see if nearfield performance improvements translated to a reduction in farfield sound pressure level, farfield experimental acoustic testing was performed on propellers that had been measured experimentally in the nearfield. The farfield results provided limited insight due to an equipment malfunction during testing. However, a large data set was obtained, which provides opportunities for future analyses. A computational simulation sought to recreate some of the nearfield experiments …

Artificial Neural Network For Predicting Heat Transfer Rates In Supercritical Carbon Dioxide, Vinusha Dasarla Giri Babu

Doctoral Dissertations and Master's Theses

Supercritical carbon dioxide as a working fluid in a closed Brayton cycle is proving to be more efficient than a conventional steam-based Rankine engine. Understanding the heat transfer properties of supercritical fluids is important for the design of a working engine cycle. The thermophysical properties of supercritical fluids tend to vary non-linearly near the pseudo-critical region. Traditionally, empirical correlations are used to calculate the heat transfer coefficient. It has been shown in the literature and within our own studies that these correlations provide inaccurate predictions near the pseudo-critical line, where heat transfer may be deteriorated or enhanced, resulting from strong …

Dynamic Analysis, Characterization, And Design Of Rigid-Flex Pcb Robotics, John Bell

All Dissertations

The era of space exploration is driven by and fuels large advances in technological progress.
Over the last decade, engineering practices for spacecraft, space structures, robotics, software and
hardware, manufacturing techniques, and the implementation of new and novel materials has been
revolutionized. Space exploration pushes the envelope in terms of technological capabilities and
robotic systems (rovers) become lighter, smaller, and more capable of sustaining damage. This
dissertation aids in the advancement of design knowledge for a class of rovers characterized by
their chassis architecture: rigid-flex printed circuit board (PCB) robotics. These rovers leverage
the printed circuit cards as the structural …

Compact Electrospray Propulsion Systems For Small Form-Factor Satellites: An Orbital Performance Survey & Platform Design, Alberto Meza

Open Access Theses & Dissertations

Over the past decades, small form-factor satellites such as CubeSats have remained as one of the most accessible platforms to reach space for universities, research institutions, private and governmental entities to perform a wide range of missions. This paper presents a survey into the design and implementation of an electrospray rail thruster, to be integrated to the CubeSat platform. The design investigated features propellant tanks for each individual thruster embedded inside the rail of a standard 1U CubeSat. The capabilities of utilizing the electrospray thruster as an attitude & determination control system was also investigated in which, a pointing accuracy …

Cryogenic Flow Boiling Heat Transfer On Additively Manufactured Liquid Rocket Engine Cooling Channels, Debra Jazmin Ortega

Open Access Theses & Dissertations

The enhancement of flow boiling heat transfer is critical because it can solve thermal management issues seen across all engineering and manufacturing applications. Even though advancements are being made, more studies are needed to understand the behavior of forced convective boiling further.Currently, there are four major issues in the field of regenerative cooling of liquid rocket engines. 1. The cooling channels are typically manufactured using conventional machining, while aerospace industries are currently exploring the additive manufacturing approach. 2. The experimental critical heat flux values for cryogenic fluids are either lower or very close to the model predictions; however, the effect …

Computational Fluid Dynamics Modeling Of Hemodialysis In Patients With An Arteriovenous Fistula, Maximilian Roth

McKelvey School of Engineering Graduate Student Theses & Dissertations

With the advent of arteriovenous fistula (AVF) for use in hemodialysis, the anastomosis built for such use has become a central point of the study to understand the flow and wall shear stresses in such a system since very large wall shear stresses can lead to arterial/vein rupture. Considering the commonly used creation site of an anastomosis as connecting the radial artery to the cephalic vein, a model is created to calculate the wall shear stresses across various components of the system. The model depicts a connection of the specified vein and artery bridged together allowing the increase in blood …

Comparison Of Stability And Control Characteristics Of The Pipistrel Virus Sw And Pipistrel Velis Electro, Sean Gregory Gunther

Theses and Dissertations

This document finds the stability and control affects of electric powerplant conversion on a pre-existing internal combustion powered Pipistrel Virus SW through comparison with the Pipistrel Velis Electro. Testing included analysis of both static and dynamic stability on the longitudinal and lateral-directional axes of the airplane. Due to the light sport airplane being used in testing, some of the intedended tests were unable to be performed, however, conclusions were still capable of being made. The primary conclusion is that electric conversion of an airframe has no significant negative consequences, with the airplane still exhibiting positive stability on all three axes. …

Piper Pa-28-181 Archer Iii Tail #931ec Flight Test Stability, Control And Performance, Steven Allan Sutton

Theses and Dissertations

The following flight test was conducted as part of the culmination requirement for the Master of Science, Flight Test Engineer degree program from Florida Institute of Technology. The flight was conducted to gather data and produce a flight test report on the data gathered. The flight test plan consisted of a series of both Stability and Handling test point as well as basic aircraft performance points. The testing was planned to be accomplished over a single flight, for reasons discussed later in this report. The flight departed on the morning of 26 September, 2022 out of Bob Sikes Airport, KCEW, …

Developmental Evaluation Of The B-1b Aircraft, Jonathon Malycke

Theses and Dissertations

The purpose of this test was to perform a Developmental Phase IIA evaluation of the B-1B Lancer for the land-based, long-range, all-weather ground attack mission. One two-hour ground evaluation, one simulator and one flight totaling 7.5 hours was conducted under daylight, visual meteorological conditions from Dyess Air Force Base (AFB) in Abilene, Texas (337th Test and Evaluation Squadron). All test objectives were completed except the low altitude flight evaluation, landing pattern operations, and AFCS operations due to weather, maintenance and time constraints. The test aircraft was representative of a production B-1B aircraft and included a Sniper Targeting Pod and a …

Stress-Based Topology Optimization Of Pi Preform-Bonded Composite Laminate Structure, Iwan Broodryk

Theses and Dissertations

The purpose of this work is to explore the stress-based topology optimization of structure that utilizes laminated composites and 3D woven Pi preform joints. Simple geometry, loading, and boundary conditions are considered. At a finite element level, an aggregate stress ratio is developed for Pi joint and acreage laminate elements. A basic descent method of moving asymptotes (BDMMA) algorithm is created to solve all optimization problems. Topology results for two different stress-based formulations and a compliance minimization problem are compared, followed by an in-depth analysis at a Pi joint and laminate level.

Analysis Of Proposed Active Radiation Shielding Design Concept For Spacecraft, Claire Mechmann

Theses and Dissertations

A need exists to protect the crew of interplanetary spacecraft from lethal doses of Galactic Cosmic Radiation (GCR) and Solar Energetic Particles (SEPs). As plans progress to send humans beyond lower Earth orbit (LEO) and outside of Earth’s protective magnetosphere, agencies involved in this endeavor find themselves confronted with the obstacle of shielding the crew from this harmful radiation. A proposed active shielding concept design has been suggested, utilizing charged dielectric capacitors to deflect incoming charged particles. This analysis will examine the feasibility of the proposed design and offer potential materials useful for application. The results should prove informative for …

2022 Summer-Fall Graduate Recognition Program, Propulsion Research Center, Robert Frederick

PRC Graduate Recognition

This program includes the graduate recognition program for summer and fall 2022. Includes photographs, upcoming events, recent publications, and student profiles.

Carbon Fibers From Bio-Based Precursors Derived From Renewable Sources, Sagar Kanhere

All Dissertations

Carbon fibers have the highest strength and modulus among all known fibers and are used as reinforcements in high-performance composites [1]. Carbon fibers also have a very low density relative to metals. Therefore, carbon fibers possess ultrahigh specific strength and modulus, which make them desirable for high-performance light-weight composites. A vast majority of commercial carbon fibers are produced from PAN precursors that are expensive, which limits the use of PAN-derived carbon fibers to aerospace applications (e.g., airplanes). However, for costsensitive applications, there is a need for low-cost, moderate performance carbon fibers. Lignin is a low-cost by-product of pulping and biorefining …

Advanced Generalized Predictive Control And Its Application To Tiltrotor Aircraft For Stability Augmentation And Vibration Reduction, Thomas Glen Ivanco

Mechanical & Aerospace Engineering Theses & Dissertations

The goals of this research were to restore generalized predictive control (GPC) capability at NASA and within the community, to better understand GPC and its performance relative to other options, and to improve upon the capability of GPC. Unique to this research is the comparison of GPC with other control options including PID controllers, optimal control theory, and other versions of the similar AutoRegressive moving average model with eXogenous inputs (ARX) models. Similar to GPC, ARX models use an experimentally acquired system identification to characterize the input/output relationship between controls and response measurements. Because this relationship is determined from acquired …

Characterizing Climb And Propeller Performance For A Fixed Pitch, Single-Engine, Electric Aircraft, Austin Lawrence Andwan

Theses and Dissertations

Electric aircraft are on the horizon. Both industry and regulators have an abundance of flight tests ahead to ensure safe operation of these new aircraft. Conventional performance standards regaurding edurance, climb performance and cruise conditions are largely not applicable to assessing an electrically propulsed aircraft. While battery technologies are the current barrier for electric aircraft, there also hasn’t been much flight testing to reveal their unique performance trends. This experiment focus’s on characterizing some of these performance trends obtained through a level flight and climb test in the Pipistrel Velis Electro. The rate-of-climb did not exhibit a decrease when the …

A Theoretical Trade-Off Between Wave Drag And Sonic Boom Loudness Due To Equivalent Area Changes On A Supersonic Body, Nolan L. Dixon

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The NASA University Leadership Initiative (ULI) titled ”Adaptive Aerostructures for Revolutionary Civil Supersonic Transportation” consists of a team of university and industry partners studying the feasibility of reducing the perceived loudness of the sonic boom by introducing an adaptive geometry at localized regions of an aircraft’s outer-mold line. The Utah State University AeroLab is a member of this ULI team and has produced low-fidelity tools to predict the aerodynamic and boom loudness effects from localized changes to the geometry.

Such changes to the geometry affect both the sonic boom loudness and wave drag; however, the precise relationship between boom loudness …

Lifting-Line Predictions For Life And Twist Distributions To Minimize Induced Drag In Ground Effect, Kyler Church

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The elliptic lift distribution produces the minimum induced drag for a given wingspan and desired lift outside of ground effect. This distribution can be generated on any wing by using geometric and/or aerodynamic twist. However, in ground effect, the elliptic lift distribution is not necessarily that which minimizes induced drag. The present work uses a modern numerical lifting-line algorithm to evaluate how the optimum lift distribution varies as a function of height above ground. The algorithm is also used to obtain the twist distributions that should be applied to wings of varying aspect ratios and taper ratios to produce the …

Dynamic Perimeter Movement Using Uavs And Robotic Systems, Nayeli Barrett, John Lawson, Billy Kihei

Symposium of Student Scholars

For this study, we propose a Dynamic Perimeter Movement system that has a user-operated UAV to identify GPS coordinate points using land markers such as April Tags. These markers would be used to identify the perimeter of a road work zone. Once the work zone is determined, autonomous robotic traffic cones would disperse to position themselves around the perimeter determined by coordinate points. As the work zone progresses the UAV would periodically update the perimeter to reposition robotic traffic cones. These traffic cones will operate using a Pure Pursuit system as a means to navigate.

Bringing Science Into The Classroom With Lora Radiotechnology, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Bringing Science Into the Classroom With LoRa Radiotechnology" from November 24, 2022.

Gen. Thomas P. Stafford Looks At The Display In The Hallway At Stafford Elementary, Weatherford Daily News

Articles

Gen. Thomas P. Stafford looks at the display in the hallway at Stafford Elementary, which is named in his honor. His two sons, Stas, right, and Michael look on.

Unless stated otherwise within this repository collection, all materials are shared under the following Creative Commons license: [Creative Commons Attribution-NonCommercial 4.0 International License].

Gen. Thomas P. Stafford Elementary School And Weatherford Stafford Airport Terminal Dedications November 21 & 22, 2022, Weatherford Daily News

Articles

A collection of photos from the dedications of Stafford Elementary and Stafford Airport Terminal, seen in the November 23rd, 2022 issue of the Weatherford Daily News.

Unless stated otherwise within this repository collection, all materials are shared under the following Creative Commons license: [Creative Commons Attribution-NonCommercial 4.0 International License].

Spacecraft Systems & Navigation, Christopher Vanacore

Student Works

This textbook is steered towards higher educational course entailed in Commercial Space Operations. This textbook will be covering in detail Orbital Satellites, and Spacecraft. These topics are discussed according to their application, design, and environment. The power system, shielding and communication systems are reviewed along with their missions, space, environment and limitations. Any vehicle, whether manned or unmanned, intended for space travel is a spacecraft. A spacecraft's required systems and equipment depend on the information it will acquire and the tasks it will perform. Although their levels of sophistication vary widely, they re all subject to the harsh conditions of …

Space Science In Manned Space Flight, Deep Space Exploration And Scientific Satellite Programs, Ji Wu

Bulletin of Chinese Academy of Sciences (Chinese Version)

In order to implement President Xi's instruction on promoting space science, space technology, and space application all together, national space programs have been developed fast, which are witnessed recently. Space science has become the hot research topic for more and more universities and research institutions. Nevertheless, there are still questions and puzzles about how could space science play its role in manned spaceflight, deep space exploration, and scientific satellites. This paper discusses the role of space science in all three kinds of space programs, starting from the history of space science, and the characteristics of manned space flight, deep space …

Development Status And Enlightenment Of Space-Time Reference For Space Activities, Weigang Xiao, Zhaoxiang Qi

Bulletin of Chinese Academy of Sciences (Chinese Version)

In this paper, the connotation of space-time reference and its relationship with space activities are described comprehensively. Time system, celestial reference frame, planetary ephemeris and pulsar timing are outlined. The gap between China and abroad development on space-time reference and its causes are analyzed. At the end, some suggestions for future development in China are proposed.

Weatherford Stafford Airport Celebrates New Terminal, Weatherford Daily News

Articles

The City of Weatherford and Oklahoma Aeronautics Commission will host a special public celebration and ribbon cutting of the new Weatherford Stafford Airport Terminal.

Unless stated otherwise within this repository collection, all materials are shared under the following Creative Commons license: [Creative Commons Attribution-NonCommercial 4.0 International License].

Stafford Highlights - Famed Astronaut Returns For 40th Anniversary Of Apollo Mission, Weatherford Daily News

Articles

Above, Lt. Gen. Thomas P. Stafford speaks during the anniversary event in Weatherford December 7, 2012, of Apollo 17.

At top right, Michael, Thomas and Stas Stafford are pictured with Cosmonaut Valery Kubasov during the 40th Anniversary of Apollo 17 December 7, 2012.

Unless stated otherwise within this repository collection, all materials are shared under the following Creative Commons license: [Creative Commons Attribution-NonCommercial 4.0 International License].