Open Access. Powered by Scholars. Published by Universities.®

Aerospace Engineering Commons™

Open Access. Powered by Scholars. Published by Universities.®

Discipline
Institution
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 2401 - 2430 of 11196

Full-Text Articles in Aerospace Engineering

Analysis Of Propeller Designs Focusing On Lowering Sound Pressure Level Through Reduced Tip Loading, Luca A. Zeitvogel Dec 2022

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 …


Computational Fluid Dynamics Modeling Of Hemodialysis In Patients With An Arteriovenous Fistula, Maximilian Roth Dec 2022

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 …


A Mechanically Intelligent Hosing-Drone, Blake Hament Dec 2022

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 …


A Theoretical Trade-Off Between Wave Drag And Sonic Boom Loudness Due To Equivalent Area Changes On A Supersonic Body, Nolan L. Dixon Dec 2022

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 …


The Design And Development Of A Miniature Gridded Ecr Ion Thruster, Nicholas Nuzzo Dec 2022

The Design And Development Of A Miniature Gridded Ecr Ion Thruster, Nicholas Nuzzo

Masters Theses

Plasma propulsion, a specific subset of electric propulsion (EP), is a class of space propulsion that produces plasma by excitation of a propellant at or above its ionization energy. This ionized propellant is then accelerated by an externally applied field (magnetic and/or electric) and produces thrust. There is an increasing need for miniaturization in spacecraft technology and the use of plasma EP devices in space propulsion. These systems provide an advantage over traditional chemical propulsion solutions which are less efficient and have more mass. Miniaturization of EP devices allows missions to have more space and mass available for their payloads …


Advanced Generalized Predictive Control And Its Application To Tiltrotor Aircraft For Stability Augmentation And Vibration Reduction, Thomas Glen Ivanco Dec 2022

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 …


Stress-Based Topology Optimization Of Pi Preform-Bonded Composite Laminate Structure, Iwan Broodryk Dec 2022

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 Dec 2022

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 …


Piper Pa-28-181 Archer Iii Tail #931ec Flight Test Stability, Control And Performance, Steven Allan Sutton Dec 2022

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 Dec 2022

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 …


A Comparative Evaluation Of Oxidation And Combustion Phenomena In Ti-6al-4v Exposed To Earth Re-Entry And Arc-Jet Test Environments, Arlene Smith Dec 2022

A Comparative Evaluation Of Oxidation And Combustion Phenomena In Ti-6al-4v Exposed To Earth Re-Entry And Arc-Jet Test Environments, Arlene Smith

Open Access Theses & Dissertations

The Ti-6Al-4V alloy is widely used in aerospace applications for its beneficial combination of properties. However, this alloy has high solubility for oxygen and thus a high reactivity. Recovered data contained within the Columbia artifacts suggests that this alloy underwent an accelerated degradation and combustion reaction when exposed to the high enthalpy, low-pressure surroundings experienced during reentry into Earth's atmosphere. Arc-jet testing has provided a simulated aerothermodynamic heating environment to mimic what the spacecraft endured. When the effect of thermal alteration on this alpha-beta phase alloy was investigated during previous studies, optical metallography and microhardness tests revealed inconsistencies between samples …


Compact Electrospray Propulsion Systems For Small Form-Factor Satellites: An Orbital Performance Survey & Platform Design, Alberto Meza Dec 2022

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 …


Dynamic Analysis, Characterization, And Design Of Rigid-Flex Pcb Robotics, John Bell Dec 2022

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 …


Dynamic Perimeter Movement Using Uavs And Robotic Systems, Nayeli Barrett, John Lawson, Billy Kihei Nov 2022

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 Nov 2022

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 Nov 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 Nov 2022

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 Nov 2022

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 Nov 2022

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 Nov 2022

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 Nov 2022

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 Nov 2022

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].


Astronaut Snoopy’S 50-Plus Year History With Nasa, Weatherford Daily News Nov 2022

Astronaut Snoopy’S 50-Plus Year History With Nasa, Weatherford Daily News

Articles

"Unknown to many, Snoopy has been working with NASA since the late 1950s"


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].


New Schools Personal For Project Manager, Weatherford Daily News Nov 2022

New Schools Personal For Project Manager, Weatherford Daily News

Articles

Gen. Thomas P. Stafford Elementary started construction in 2020, having a hand in building Stafford Elementary and East Intermediate was personal for Project Manager Shawn Bonner.


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].


A Machine Learning Approach Towards Analyzing Impact Of Surface Weather On Expect Departure Clearance Times In Aviation, Dothag Truong, Shlok Misra, Godfrey V. D'Souza Nov 2022

A Machine Learning Approach Towards Analyzing Impact Of Surface Weather On Expect Departure Clearance Times In Aviation, Dothag Truong, Shlok Misra, Godfrey V. D'Souza

Publications

Commercial air travel in the United States has grown significantly in the past decade. While the reasons for air traffic delays can vary, the weather is the largest cause of flight cancellations and delays in the United States. Air Traffic Control centers utilize Traffic Management Initiatives such as Ground Stops and Expect Departure Clearance Times (EDCT) to manage traffic into and out of affected airports. Airline dispatchers and pilots monitor EDCTs to adjust flight blocks and flight schedules to reduce the impact on the airline’s operating network. The use of time-series data mining can be used to assess and quantify …


Local Astronaut May Command U.S.-Russian Flight (Reprint From 1972), Weatherford Daily News Nov 2022

Local Astronaut May Command U.S.-Russian Flight (Reprint From 1972), Weatherford Daily News

Articles

EDITOR’S NOTE: this story first appeared in the November 2, 1972, edition of the Weatherford Daily News, 50 years ago today, about Lt. Gen. Thomas P. Stafford’s chance to commence a U.S.-Russian space flight.


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].


Ramping Up For Cost And Performance Improvements, Arthur Zucchetti Lechmann, Guilherme Henrique Lima, João Paulo Lucchi, Paulo Henrique Azevedo Santana, Pedro Kamikihara Nov 2022

Ramping Up For Cost And Performance Improvements, Arthur Zucchetti Lechmann, Guilherme Henrique Lima, João Paulo Lucchi, Paulo Henrique Azevedo Santana, Pedro Kamikihara

Student Works

The objective of this Research Project was to study the possible benefits of developing an improved Metering Control System. This study identified potential cost savings and reduced emissions through the greater use of a Metering Control System. The results of this research have indicated an annual cost reduction of $720,000 in fuel burn and a significant delay time reduction caused by accumulated ground traffic. In addition, during peak hours, it was concluded that savings could be potentially higher. Therefore, by optimizing the ground movement, it is also expected a lower level of CO2 emissions, an increased safety level due to …


Elastomer O-Ring Seal Swell Measurements For Sustainable Aviation Fuel Material Compatibility, Conor J. Faulhaber Nov 2022

Elastomer O-Ring Seal Swell Measurements For Sustainable Aviation Fuel Material Compatibility, Conor J. Faulhaber

Honors Theses

As efforts continue to fight climate change by transitioning energy sources away from fossil fuels and towards renewable alternative, the commercial aviation sector finds itself at danger of falling behind in emissions reductions. To combat this, the best term opportunity to reduce the industry’s contribution to greenhouse gas emissions has been identified as sustainable aviation fuel, or SAF, derived from renewable feedstocks like agricultural waste or used cooking oil. Currently, SAF is regulated to a 50%v blending limit with conventional petroleum-based fuel to maintain certain jet fuel properties, including material compatibility with elastomer o-ring seals. When these seals come in …


Testing And Verification For The Open Source Release Of The Horizon Simulation Framewortesting And Verification For The Open Source Release Of The Horizon Simulation Framework, William J. Balfour Nov 2022

Testing And Verification For The Open Source Release Of The Horizon Simulation Framewortesting And Verification For The Open Source Release Of The Horizon Simulation Framework, William J. Balfour

Master's Theses

Modeling and simulation tools are exceptionally useful for designing aerospace systems because they allow engineers to test and iterate designs before committing the massive resources required for system realization. The Horizon Simulation Framework (HSF) is a time-driven modeling and simulation tool which attempts to optimize how a modeled system could perform a mission profile. After 15 years of development, the HSF team aims to achieve a wider user and developer base by releasing the software open source. To ensure a successful release, the software required extensive testing, and the main scheduling algorithm required protections against new code breaking old functionality. …


Multi-Robot Symbolic Task And Motion Planning Leveraging Human Trust Models: Theory And Applications, Huanfei Zheng Nov 2022

Multi-Robot Symbolic Task And Motion Planning Leveraging Human Trust Models: Theory And Applications, Huanfei Zheng

All Dissertations

Multi-robot systems (MRS) can accomplish more complex tasks with two or more robots and have produced a broad set of applications. The presence of a human operator in an MRS can guarantee the safety of the task performing, but the human operators can be subject to heavier stress and cognitive workload in collaboration with the MRS than the single robot. It is significant for the MRS to have the provable correct task and motion planning solution for a complex task. That can reduce the human workload during supervising the task and improve the reliability of human-MRS collaboration. This dissertation relies …