Engineering Commons^™

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 …

Practical Applications Of Pressure-Fed Lox/Ch4 Rocket Engines, James Susen Parks

Open Access Theses & Dissertations

The University of Texas at El Paso Aerospace Center is working on a family of LOX/CH4 pressure-fed rocket engines. The applications of a pressure-fed rocket engine include orbital launch vehicles and lunar ascent and descent vehicles. This dissertation focuses on the application of the CROME LOX/CH4 engines under development at UTEP. The dissertation contains three chapters on orbital launch vehicles and a fourth chapter on lunar descent/ascent vehicles. The first two chapters look at pressure-fed LOX/CH4 orbital launch vehicle design compared to an electric pump fed and a gas generator vehicle. The third chapter looks at the sensitivities in the …

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.

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 …

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 …

Design And Analysis Of Electrical Power And Communication Systems For 3u Sealion Cubesat Mission, Joseph D. Siciliano

Electrical & Computer Engineering Theses & Dissertations

Old Dominion University (ODU) Space Systems students in conjunction with the United States Coast Guard Academy (USCGA) are designing and developing a 3U Very Low Earth Orbit (VLEO) CubeSat mission aptly named SeaLion. This work specifically details the design of the Electrical Power System (EPS) and Communication System of the satellite. Electrical power in orbit is a precious commodity and must be carefully regulated and distributed to ensure the satellite’s operational health. Commonly, CubeSat electrical power is retained in orbit via outward facing solar cells and stored in onboard rechargeable batteries. This thesis proposes using non-rechargeable primary battery cells and …

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 …

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 …

Implementation Of An Extended Kalman Filter Using Inertial Sensor Data For Uavs During Gps Denied Applications, Sky Seliquini

Mechanical & Aerospace Engineering Theses & Dissertations

Unmanned Aerial Vehicles (UAVs) are widely used across the industry and have a strong military application for defense. As UAVs become more accessible so does the increase of their applications, now being more limited by one’s imagination as opposed to the past where micro electric components were the limiting factor. Almost all of the applications require GPS or radio guidance. For more covert and longer range missions relying solely on GPS and radio is insufficient as the Unmanned Aerial System is vulnerable to malicious encounters like GPS Jamming and GPS Spoofing. For long range mission GPS denied environments are common …

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 …

A Study Of Asymmetric Supersonic Wind Tunnel Nozzle Design, Brittany A. Davis

Mechanical & Aerospace Engineering Theses & Dissertations

Achieving higher Mach numbers for private and commercial flight is a growing interest in the aerospace community. To qualify vehicles prior to flight, tests must be run in wind tunnels. Asymmetric wind tunnel nozzles are of continuing interest to the aerospace community due to their ability to change throat geometry, allowing for a range of Mach numbers to be achieved that encompasses all of the supersonic regime. The sliding block wind tunnel at Old Dominion University (ODU) is designed for a range of Mach numbers from about 1.8 to 3.5 but is limited to an upper limit of 2.8 by …

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 …

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 …

Residual Strength Estimation Of Degraded Bonded Joints Based On Non-Destructive Evaluations, Guilherme Garcia Momm

Theses and Dissertations

Pioneer designers acknowledged structural bonding advantages over other joining methods, sparking many aerospace applications. Nonetheless, durability issues, weak bonds, and the inability to non-destructively interrogate bond quality after-the-fact hindered widespread bonding use. These challenges also contributed to several aircraft accidents, fostering extensive related research. Firstly, we examined the bonding operational history in aviation. The challenge to simulate or experimentally reproduce bonded joints’ long-term behavior under real-life conditions magnifies the value of in-service data. Since 1944 the International Civil Aviation Organization has recommended investigating aircraft incidents/accidents. Among numerous investigation reports publicly available, we identified 73 bond-related occurrences involving type-certified aircraft registered …

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 …

Computer Vision Of Analog Gauges As An Alternative To Digital Flight Test Instrumentation, Michael William James

Theses and Dissertations

Currently, there are a couple of options to gather stick force data from flight test aircraft. Either the aircraft is instrumented with costly piezoelectric force sensors and recorders integrated into the aircraft stick, or the test pilot must use a traditional analog stick force gauge with a pointer and telltale. The conventional stick force gauge works well when the pilot has the mental and physical bandwidth to read and remember, or record, the stick force values throughout the maneuver but does not suffice when in a task saturated, high g force maneuver such as the windup turn. This project proposes …

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 …

Rotating Detonation Rocket Engine Fluidic Diode Injector Studies, Allison Brooke Lentz

Honors Capstone Projects and Theses

No abstract provided.

Honor Capstone Lunar Logistics Study, Owen Bradley Cox

Honors Capstone Projects and Theses

No abstract provided.

Computational Plasma Modeling For Characterization Of An Atmospheric Pressure Plasma Jet, Declan George Brick

Honors Capstone Projects and Theses

No abstract provided.

A Primer For Designing A Small Spacecraft Mission Operations Architecture, Joseph M. A. Feliciano

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Joseph M. A. Feliciano on April 28, 2022.

Design And Analysis Of A Pitch Controller For An Unstable Aircraft Using A Linear Quadratic Regulator, Marco Antonio Garcia

Honors Capstone Projects and Theses

No abstract provided.

Early Warning Reentry System Comprising High Efficiency Module For Determining Spacecraft Reentry Time, Robert A. Bettinger

AFIT Patents

The present invention relates to an early warning reentry system comprising a high efficiency module for determining spacecraft reentry time and a highly efficient method for determining spacecraft reentry time. The method permits more accurate, earlier spacecraft reentry time determinations using publicly available trajectory information without the need for accounting for the actual design configuration of the spacecraft in question. Thus, a module for making such determinations can easily and inexpensively be added to an early warning reentry system.

Characterizing And Predicting Human Visual Perception Of Unmanned Aerial Vehicle Gestures, Paul Fletcher

School of Computing: Dissertations, Theses, and Student Research

Unmanned Aerial Vehicles (UAVs) are being used in public domains and hazardous environments where effective communication strategies are critical. UAV gesture techniques have been shown to communicate meaning to human observers and may be ideal in contexts that require lightweight systems such as unmanned aerial flight, however, this work may be limited to an idealized range of viewer perspectives. As gesture is a visual communication technique it is necessary to consider how the perception of a robot gesture may suffer from obfuscation or self-occlusion from some viewpoints. This thesis presents the results of three online user-studies that examine participants’ ability …

Direct Numerical Simulation Of Hypersonic Turbulent Boundary Layers: Effect Of Spatial Evolution And Reynolds Number, Junji Huang, Lian Duan, Meelan M. Choudhari

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Direct numerical simulations (DNS) are performed to investigate the spatial evolution of flat-plate zero-pressure-gradient turbulent boundary layers over long streamwise domains (Formula Presented, with Formula Presented the inflow boundary-layer thickness) at three different Mach numbers, Formula Presented, Formula Presented and Formula Presented, with the surface temperatures ranging from Quasi adiabatic to highly cooled conditions. The settlement of turbulence statistics into a fully developed equilibrium state of the turbulent boundary layer has been carefully monitored, either based on the satisfaction of the von Kármán integral equation or by comparing runs with different inflow turbulence generation techniques. The generated DNS database is …

Development Of A Bio-Inspired Artificial Butterfly Vehicle, Thomas Payne Clark

Honors Capstone Projects and Theses

No abstract provided.

Computational Analysis Of The Effects Of Scarfed Nozzle Variations On Jet Plumes, Andrew J. La Sorsa

ONU Student Research Colloquium

A computational fluid dynamics analysis investigating the variation of effects on nozzles with non-orthogonal exit planes, known as scarfing, was performed. The steady Reynolds-averaged Navier-Stokes model, coupled with the Spalart-Allmaras turbulence model, was used to simulate and compare plume development and characteristics using various scarfing geometries at variable inlet conditions. The jet plume cross-section is significantly affected for overexpanded conditions, while retaining the nozzle exit shape for underexpanded conditions, although slight peaks (bifurcation) do occur at the centerline. The same observations occur when slightly changing the angle of scarf. However, inverting the overall geometry of the diverging portion of the …

Effects Of Vortex Generator Placement On A Horizontal Axis Wind Turbine Blade, Dagan Sorensen

ONU Student Research Colloquium

Vortex generators are commonly used devices to control the flow over an airfoil or other surface. In this paper the effect of differing placements of vortex generators on a wind turbine airfoil, compared to an airfoil without vortex generators, were simulated using computational fluid dynamics(CFD). It was shown that, in some instances, the application of vortex generators effectively controlled the flow over the airfoil to increase the power produced by the wind turbine. According to the CFD results, the application of vortex generators at an angle increased the lift produced, as well as delaying the separation of the boundary layer.

Computational Comparison Of Dual Bell, Expansion-Deflection, And Aerospike Nozzles, Manuel R. Abadie Ardon

Honors College Theses

In the search for a Single-Stage-to-Orbit rocket, Altitude Compensating Nozzles concepts (ACNs) have been proposed since the 1950s, but research has stalled despite the modern analysis tools available. These nozzle concepts offer optimum performance at two or more altitude settings. This research chose three of these concepts, these being the Dual Bell, Expansion-Deflection, and Aerospike, which were designed and analyzed at various pressure ratios (NPR=10,15,30,36,30,45) using Computational Fluid Dynamics (CFD) software FLUENT. Simulations generated pressure distributions along the nozzle wall, which allowed to calculate data values such as thrust coefficients. Nozzle efficiency is calculated from this data and used to …

A Review Of Avian-Inspired Morphing For Uav Flight Control, Christina Harvey, Lawren L. Gamble, Christian R. Bolander, Douglas F. Hunsaker, James J. Joo, Daniel J. Inman

Mechanical and Aerospace Engineering Faculty Publications

The impressive maneuverability demonstrated by birds has so far eluded comparably sized uncrewed aerial vehicles (UAVs). Modern studies have shown that birds’ ability to change the shape of their wings and tail in flight, known as morphing, allows birds to actively control their longitudinal and lateral flight characteristics. These advances in our understanding of avian flight paired with advances in UAV manufacturing capabilities and applications has, in part, led to a growing field of researchers studying and developing avian-inspired morphing aircraft. Because avian-inspired morphing bridges at least two distinct fields (biology and engineering), it becomes challenging to compare and contrast …