Aerospace Engineering Commons^™

The Development And Characterization Of Piezoelectric- Magnetostrictive Smart Self-Sensing Composites, George Relebohile Qhonosheane

Mechanical and Aerospace Engineering Dissertations - Archive

The composites industry is expanding due to the growing global demand for high-performance materials. How do you ensure the production of composites is as smooth and effective as possible while maintaining the high quality of the material? The key issues in composites include crack occurrence, sticking to molds in the production process, and durability differences during their operation. However, monitoring such cases can be challenging. The industry is in need of a smart solution to be able to obtain accurate data from the raw material. This work focuses on the development of smart composite materials. The word composite comes from …

Assessment Of Contaminant Flowpaths In Airside Economization And Analysis Of Thermal Performance At Tank And Server Level For Single-Phase Immersion Cooled Data Centers, Satyam Saini

Mechanical and Aerospace Engineering Dissertations - Archive

The last two decades of 2000 have seen an explosion of utilization and reliance on digital technologies and platforms. During this time, electronic devices have undergone intense miniaturization and a corresponding rise in power densities. In parallel to these developments, data center proliferation has been driven by the increasing utility of revolutionary technologies such as Machine Learning, Artificial Intelligence, e-commerce and, the Internet of Things. Data centers, thus, have become the core of the modern digital age. The primary bottleneck, however, due to extensive device miniaturization and data center proliferation has always been thermal management. Many of the aforementioned technologies …

Development Of An Electro-Pneumatic Servo Clutch And Industry-Level Controller, Timothy Stevens

Mechanical and Aerospace Engineering Theses - Archive

This thesis covers the simulation and development of an electro-pneumatic servo clutch used on an FSAE racecar. This project utilizes a sophisticated simulation and various techniques to increase performance such as utilizing pulse-width and pulse-frequency modulation and the use of a 36V supply with constant current limiting to drive the solenoids. The clutch is actuated using a pneumatic cylinder with the internal pressure modulated using commercially available CNG fuel injectors. This thesis also describes the development of the electronic controller designed using analog circuits, as well as the integration of digital circuits to control operations such as launch control and …

Computational Reliability Analysis Of Blind Micro-Via With 3d And Axisymmetric Multi-Layer Pcb, Jayendra Bazaru

Mechanical and Aerospace Engineering Theses - Archive

Micro-via are components that are used to form connections from one layer to another in most Multilayered Printed Circuit Boards (PCBs). The failure of Micro-via has always been a concern of the electronic industry. The failures are exaggerated during the reflow process due to the high thermal loading. Electronic components have become ubiquitous in our society. It is important to take some measures to reduce (or) eliminate the failures at interconnects in the Printed Circuit Board to obtain highly reliable Input/Output (I/O). This work is based on a hypothetical belief that the possible cause of failure is an insufficient or …

Autonomous Aerial Vehicles Distributed Control And Interactive Games, Yusuf Kartal

Mechanical and Aerospace Engineering Dissertations - Archive

As the number of quadrotors and other Unmanned Aerial Vehicles (UAVs) increases in industrial and urban areas, the development of reliable engineering methods to control their behavior as they interact with each other becomes of central interest in control research. With the increase in demand for UAVs to work together, several real-life challenges need to be addressed that include the implementation, test, and validation of the control algorithms in flight test experiments. On the one hand, the interests of UAVs may be in harmony to perform certain tasks such as transportation, surveillance and reconnaissance. On the other hand, the interests …

Orbital Debris Analysis And Orbital Decay Analysis Of Arksat-2, Will Stuff

Mechanical Engineering Undergraduate Honors Theses

ARKSAT-2 is a cube satellite developed by the University of Arkansas for its second CubeSat mission. There are two objectives of the ARKSAT-2 mission. The first objective of this mission is to test a novel cold gas thruster propulsion system using water-propylene propellant. This propulsion system will be used for attitude control of the satellite. The second objective for the ARKSAT-2 mission is to test a Solid-State Inflation Balloon (SSIB) that has been designed and developed for this mission. The SSIB is designed to be a simple and cost-effective method for deorbiting the vehicle. In cube satellites, a software known …

Flight Test Of A Floatplane Modification To The C-130j Aircraft, Daniel Jacob Kulp

Theses and Dissertations

This report details the future flight test of a potential amphibious modification to the C-130J Super Hercules. The goal of the project is to enable an amphibious capability through the installation of dual floats via a truss structure attached to the fuselage. This project uses an iterative design process which leans heavily on digital engineering and subscale testing. Through the iterative design process, several float and truss versions underwent 6-degree of freedom aerodynamic simulation and finite element analyses to validate landing load limits and stability and control parameters. These simulators informed subsequent versions which underwent subscale physical testing in a …

Mechanics Of Preimpregnated Fiber Tow Deposition And Compaction, Virginia Meredith Rauch

Mechanical & Aerospace Engineering Theses & Dissertations

In additive manufacturing, such as Automated Fiber Placement (AFP), defects often develop during the deposition and compaction of preimpregnated composite material, which reduce the strength of the resultant material. It is necessary to reduce defects and have good adhesion between plies to optimize the laminate performance and reduce delamination between composite layers. The aim of this work is to study the adhesion and deformation of preimpregnated (prepreg) composite material during the deposition and compaction stage in the composite forming process and how material parameters can be used to increase laminate strength. Two types of experimentation were performed on thermoset IM7/8552 …

Deep Learning Object-Based Detection Of Manufacturing Defects In X-Ray Inspection Imaging, Juan C. Parducci

Mechanical & Aerospace Engineering Theses & Dissertations

Current analysis of manufacturing defects in the production of rims and tires via x-ray inspection at an industry partner’s manufacturing plant requires that a quality control specialist visually inspect radiographic images for defects of varying sizes. For each sample, twelve radiographs are taken within 35 seconds. Some defects are very small in size and difficult to see (e.g., pinholes) whereas others are large and easily identifiable. Implementing this quality control practice across all products in its human-effort driven state is not feasible given the time constraint present for analysis.

This study aims to identify and develop an object detector capable …

Failure Mode, Effects And Criticality Analysis Of A Very Low Earth Orbit Cubesat Mission, Robb Christopher Borowicz

Mechanical & Aerospace Engineering Theses & Dissertations

When space programs launch vehicles into orbit, multiple failures could arise throughout the mission and corrective actions are often not an option. Applying reliability engineering approaches during the design phase focuses on analyzing risk by anticipating potential failures and mitigating uncertainties in the design. Old Dominion University, in partnership with the U.S. Coast Guard Academy, and the U.S. Air Force Institute of Technology designed and developed a 3U CubeSat mission to validate on-orbit, three space technology payloads. Mission SeaLion will fly as a secondary payload on stage two of Northrop Grumman’s Antares rocket and will be deployed in a very …

2022 Spring Graduate Recognition Program, Propulsion Research Center, Robert Frederick

PRC Graduate Recognition

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

Flight Test Evaluation Of Piper Seminole, Brian-Emmanuel Hopeton Walters

Theses and Dissertations

After taking FTE 5702 – Stability and Control class, taught by Dr.Kimberlin, I understood the concept of using an aircraft and then testing how it handles in the air. Almost all flight tests done on aircraft are done by the manufacturer. Some aircraft may have a lot of comprehensive information available, while others have little to no information. It can also be hard to find the specific data that a pilot or owner desires. These various tests allow a greater understanding of aircraft stability and performance available for analysis and relating. The aircraft I flew during FTE 5702 class was …

Carbon Fiber Coil Spring Characterization And Manufacturing, Cooper Madrazo

UNLV Theses, Dissertations, Professional Papers, and Capstones

Helical coil springs are used in many mechanical design applications including industrial machines, devices, and vehicle suspension systems. It is desirable to minimize the weight of vehicle suspension systems as this can improve performance and handling. Most vehicle suspension coil springs are made from solid steel alloys or other metallic materials. Significant weight savings could be achieved if the metallic material were replaced by high performance fiber reinforced polymer composites. However, the coil spring geometry is a difficult manufacturing challenge for composite materials. The goal of this thesis was to investigate efficient and low-cost manufacturing methods to produce light-weight polymer …

Fuel Injector Design Of A Hypersonic Jet Engine Using Computational Fluid Dynamics, Melissa Rose Mercado

UNLV Theses, Dissertations, Professional Papers, and Capstones

The development of hypersonic airbreathing engines, such as a supersonic combustion ramjet, or scramjet, are implemented for flight Mach numbers over 5 where combustion must occur in supersonic conditions. The advancement of scramjet propulsion has led to favored usage over rocket propulsion systems for in atmosphere applications due to their lighter weight, higher specific impulse, and greater maneuverability [1]. The combustor section of a scramjet engine houses the fuel injectors. Fuel is injected into the supersonic flow with the main objective of achieving rapid and thorough fuel-air mixing because the residence time in the combustion chamber has a timescale of …

Viability Of Energy And Fuel Sources For Interstellar Travel; Design And Feasibility Of The Construction Of Manned Interstellar Space Shuttles, Lukas Mittelman

UNLV Theses, Dissertations, Professional Papers, and Capstones

The importance of proving the viability of interstellar transport and addressing its potential hazards and pitfalls is immense. If we do not look toward the future and examine what could be waiting for us, we are doing our children, our children’s children, and so on, a disservice. Here we must attempt to lay the groundwork for our future scientists, engineers, and adventurers. Asking and answering questions like, which propulsion and energy systems must we incorporate to send us through the cosmos? Will we utilize technologies known today, such as fossil fuel rockets, fission or fusion rockets, and antimatter drives (pion …

A Study Of Wings With Constant And Variable Sweep For Aerodynamic Efficiency In Inviscid Flow, Bruno Moorthamers

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wing sweep has been studied by industry and academia since the pioneering days of aviation for both high-speed and low-speed applications. In transonic and supersonic flight regimes it serves to delay the onset of compressibility effects and decrease wave drag. In subsonic conditions, flying wing designs sweep back the main lifting surface in such a way that it can be used for longitudinal stability and control, to allow for the elimination of a traditional empenage. This is desirable because it can decrease the aerodynamic drag. Sweep can also be seen in nature in the wings of birds and fins of …

Optimal Relative Path Planning For Constrained Stochastic Space Systems, Nathan Bohus Stastny

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rendezvous and proximity operations for automated spacecraft systems requires advanced path planning techniques that are capable of generating optimal paths. Real-world constraints, such as sensor noise and actuator errors, complicate the planning process. Operations also require flight safety considerations in order to prevent the spacecraft from potentially colliding with the associated companion spacecraft. This work proposes a new, ground-based trajectory planning approach that seeks an optimal trajectory while meeting all mission constraints and accounting for vehicle performance and safety requirements. This approach uses a closed-loop linear covariance simulation of the relative trajectory coupled with a genetic algorithm to determine fuel …

Performance Variability In Solid Rocket Motors, Manvith Amara

Honors Capstone Projects and Theses

No abstract provided.

Carbon Fiber Interleaved Polyester Laminate Strength Testing With Correlation In Finite Element Simulations, Hieu Le Huynh

Theses and Dissertations

Delamination of composite structures under impact conditions has been a catastrophic and economic issue in the past and is still a problem today. Many techniques have been used to improve the toughness in composite laminates. An example of a previous dissertation was performed by Adnan Gheryani titled: “Analysis of Polyester Interleafs for Toughness Enhancement in Composite Structures.” Gheryani’s study shows that adding in polyester interleafs into composite laminates made primarily from carbon fiber fabric adds ductility and resists crack growth after delamination, which leads to improvement of the overall toughness of the laminate. However, improvements in toughness, strength, and stiffness …

Interpolation And Extrapolation Of Optimally Fitted Kinematic Error Model For Five-Axis Machine Tools, Le Ma, Douglas A. Bristow, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Machine tool geometric errors are frequently corrected by populating compensation tables that contain position-dependent offsets to each commanded axis position. While each offset can be determined by directly measuring the individual geometric error at that location, it is often more efficient to compute the compensation using a volumetric error model derived from measurements across the entire axis space. However, interpolation and extrapolation of measurements, once explicit in direct measurement methods, become implicit and obfuscated in the curve-fitting process of volumetric error methods. The drive to maximize model accuracy while minimizing measurement sets can lead to significant model errors in workspace …