A Survey And Performance Analysis Of Orbit Propagators For Leo, Geo, And Highly Elliptical Orbits,
2017
Utah State University
A Survey And Performance Analysis Of Orbit Propagators For Leo, Geo, And Highly Elliptical Orbits, Simon P. Shuster
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
On-orbit targeting, guidance, and navigation relies on state vector propagation algorithms that must strike a balance between accuracy and computational efficiency. To better understand this balance, the relative position accuracy and computational requirements of numerical and analytical propagation methods are analyzed for a variety of orbits. For numerical propagation, several differential equation formulations (Cowell, Encke-time, Encke-beta, and Equinoctial Elements) are compared over a range of integration step sizes for a given set of perturbations and numerical integration methods. This comparison is repeated for two numerical integrators: a Runge-Kutta 4th order and a NLZD4/4. For analytical propagation, SGP4, which relies on …
Evaluation Of Flux Correction On Three-Dimensional Strand Grids With An Overset Cartesian Grid,
2017
Utah State University
Evaluation Of Flux Correction On Three-Dimensional Strand Grids With An Overset Cartesian Grid, Dalon G. Work
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Simulations of fluid flows over complex geometries are typically solved using a solution technique known as the overset meshing method. The geometry is meshed using grid types appropriate to the local geometry in a patchwork fashion, rather than meshing the entire geometry with one type of mesh. The strand-Cartesian approach is a simplification of this process. While high-order accurate solvers on Cartesian grids are simple to implement, strand grids are usually restricted to second-order accuracy, resulting in poor quality solutions. Flux correction is a high-order accurate solution method, specifically designed for use on strand grids. The flux correction method on …
Single Waypoint Zem/Zev Based Closed-Loop Controller Design For Rendezvous With A Rotating Target,
2017
Florida Institute of Technology
Single Waypoint Zem/Zev Based Closed-Loop Controller Design For Rendezvous With A Rotating Target, Armando Alvarez Rolins
Theses and Dissertations
The research presented in this thesis addresses a very specific kind of autonomous rendezvous procedure between two spacecraft in close proximity, namely that in which the chaser object is attempting to dock at a location on a rotating target which is tracing a circle perpendicular to the axis of rotation. The approaches that have been mentioned in literature which focus on this specific condition make use of offline optimization algorithms to plot the trajectory of the chaser and use closed-loop control to follow that trajectory. This method is computationally demanding and does not allow for feedback in the desired boundary …
Characterization Of The Thermal Resistance Of Grain Boundaries Of Cerium Oxide,
2017
Utah State University
Characterization Of The Thermal Resistance Of Grain Boundaries Of Cerium Oxide, Jesse Spackman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Many materials are made up of small crystals, or grains. Grain boundaries are the interfaces between two grains and affect the flow of heat through the material. These interfaces serve to interfere with the energy carriers by scattering or disrupting them. Because of the negative effect these interfaces have on these energy carriers, they inhibit heat flow and act as thermal resistors. The thermal boundary resistance between two grains of the same material is sometimes referred to as the Kapitza resistance, although this term is also used to describe the thermal resistance between solid/solid interfaces of different materials or solid/liquid …
Water Entry Impact Dynamics Of Diving Birds,
2017
Utah State University
Water Entry Impact Dynamics Of Diving Birds, Saberul Islam Sharker
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Plunge diving and surface diving are two main techniques used by seabirds for foraging purposes. While some plunge divers can dive into the water at very high speeds (24 m/s), surface divers do not. This study analyzes the free-surface impact of 3D printed bird head models with embedded accelerometers to determine why surface divers cannot dive safely at high speeds. The problem is investigated in the context of impact jerk where surface divers, unlike plunge divers, are found to experience non-dimensional jerk (J∗) values exceeding a safe limit. This approach portrays itself as an unconventional yet effective method …
Mechanical Performance Of Natural / Natural Fiber Reinforced Hybrid Composite Materials Using Finite Element Method Based Micromechanics And Experiments,
2017
Utah State University
Mechanical Performance Of Natural / Natural Fiber Reinforced Hybrid Composite Materials Using Finite Element Method Based Micromechanics And Experiments, Muhammad Ziaur Rahman
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A micromechanical analysis of the representative volume element (RVE) of a unidirectional flax/jute fiber reinforced epoxy composite is performed using finite element analysis (FEA). To do so, first effective mechanical properties of flax fiber and jute fiber are evaluated numerically and then used in evaluating the effective properties of flax/jute/epoxy hybrid composite. Mechanics of Structure Genome (MSG), a new homogenization tool developed in Purdue University, is used to calculate the homogenized effective properties. Numerical results are compared with analytical solution based on rule of mixture, Halpin-Tsai as well as Tsai-Hahn equations. The effect of the volume fraction of the two …
Implementing Delay-Tolerant Networking At Morehead State University,
2017
Morehead State University
Implementing Delay-Tolerant Networking At Morehead State University, Nathaniel J. Richard
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 Nathaniel J. Richard on April 28, 2017.
Flying Simple Experiments In Space,
2017
Morehead State University
Flying Simple Experiments In Space, Robert J. Twiggs
Robert "Bob" Twiggs STEM Education Collection
A PowerPoint presentation created by Professor Bob Twiggs titled "Flying Simple Experiments in Space" from April 28, 2017.
Study Of Custom Tool Control In Aviation And Aerospace And Selection Of Materials And Manufacturing Process,
2017
Morehead State University
Study Of Custom Tool Control In Aviation And Aerospace And Selection Of Materials And Manufacturing Process, Ethan C. Rowley
Morehead State Theses and Dissertations
A thesis presented to the faculty of the College of Business and Technology at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Ethan C. Rowley on April 27, 2017.
Providing A Unique Stem Education Opportunity With A Five Day Eleomission,
2017
Morehead State University
Providing A Unique Stem Education Opportunity With A Five Day Eleomission, Robert J. Twiggs, Amin Djamshidpour, Matt Craft, Dale Nash, Hank Voss
Robert "Bob" Twiggs STEM Education Collection
A PowerPoint presentation created by Robert Twiggs, Amin Djamshidpour, Matt Craft, Dale Nash, and Hank Voss titled "Providing a Unique STEM Education Opportunity with a Five Day ELEOMission" from April 26, 2017.
Software Requirements Specification For Lunar Icecube,
2017
Morehead State University
Software Requirements Specification For Lunar Icecube, Michael R. Glaser-Garbrick
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 Master of Science by Michael R. Glaser-Garbrick on April 21, 2017.
Computer Simulation Of The Attitude Of Lunar Icecube During Early Operations And Deployment,
2017
Morehead State University
Computer Simulation Of The Attitude Of Lunar Icecube During Early Operations And Deployment, Johnathon F. Fitzpatrick
Morehead State Theses and Dissertations
A Thesis Presented to the Faculty of the College of Science Morehead State University in partial fulfillment of the requirements for the degree of Master of Science by Jonathan F. Fitzpatrick on April 21, 2017.
An Evaluation Of The Relationships Between Collegiate Aviation Safety Management System Initiative, Self-Efficacy, Transformational Safety Leadership And Safety Behavior Mediated By Safety Motivation,
2017
University of North Dakota
An Evaluation Of The Relationships Between Collegiate Aviation Safety Management System Initiative, Self-Efficacy, Transformational Safety Leadership And Safety Behavior Mediated By Safety Motivation, Daniel Kwasi Adjekum
International Journal of Aviation, Aeronautics, and Aerospace
The study conceptualized Safety Management System (SMS) initiative, self-efficacy, and transformational safety leadership as constructs that relates to safety behavior (measured by safety compliance and safety participation) when mediated by safety motivation using a quantitative approach. Structural equation modeling techniques was used to derive a final measurement model that fit the empirical data and was used to test the study hypotheses. Utilizing a sample of 282 collegiate flight students and instructors from a large public university in the US, a 46-item survey was used to measure respondent’s perceptions on the study variables. The results indicate that perceptions of SMS policy …
2u Cubesat Structural Design And Integration,
2017
Morehead State University
2u Cubesat Structural Design And Integration, Yevgeniy Byeloborodov
Morehead State Theses and Dissertations
A thesis presented to the faculty of the College of Science, Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Yevgeniy Byeloborodov on April 18, 2017.
System And Method For Robust Nonlinear Regulation Control Of Unmanned Aerial Vehicles Synthetic Jet Actuators,
2017
Embry-Riddle Aeronautical University
System And Method For Robust Nonlinear Regulation Control Of Unmanned Aerial Vehicles Synthetic Jet Actuators, Vladimir V. Golubev, William Mackunis
Publications
An unmanned aerial vehicle (UAV) is provided with a plurality of synthetic jet actuators and a nonlinear robust controller. The controller compensates for uncertainty in a mathematic model that describes the function of the synthetic jet actuators. Compensation is provided by the use of constant feedforward best guess estimates that eliminate the need for more highly computationally burdensome approaches such as the use of time-varying adaptive parameter estimation algorithms.
Concept Study Of A Reusable Suborbital Launch Vehicle (Rslv),
2017
University of Alabama in Huntsville
Concept Study Of A Reusable Suborbital Launch Vehicle (Rslv), Jared Fuchs, Matthew Haskell, Benjamin Thompson, William Hankins
Research Horizons Day Posters
No abstract provided.
Determining The Translational Velocity Of Flying Objects Using Ultrasonic Sensors,
2017
University of Alabama in Huntsville
Determining The Translational Velocity Of Flying Objects Using Ultrasonic Sensors, Alex Christley
Research Horizons Day Posters
No abstract provided.
Satellite Sequencing Optimization Using A Genetic Algorithm,
2017
Western Michigan University
Satellite Sequencing Optimization Using A Genetic Algorithm, Andrew Verstraete
Research and Creative Activities Poster Day
The problem of mission design for a robotic servicing satellite in geosynchronous Earth orbit (GEO) was investigated. A representative set of potential client satellites was selected, and operational needs were randomly assigned based on the average number of GEO retirements, anomalies, and repositioning maneuvers that currently occur each year. An objective function was developed to represent the value of servicing mission sequences, including client fees, time penalties, and operational risk. A genetic algorithm was then used to find sequences of operations on the potential client set that maximized the objective function’s value. Scenarios were analyzed with the database of satellites …
Method And Shear-Driven Micro-Fluidic Pump,
2017
Minnesota State University, Mankato
Method And Shear-Driven Micro-Fluidic Pump, Nihad E. Daidzic
Aviation Department Publications
United States Patent Application, Publication Number US 2017/0096990 A1, Publication Date April 6, 2017.
An example includes an apparatus to pump a fluid. The apparatus includes a housing extending along a length defining an elongate interior, an actuator in the housing, conforming to the elongate interior, the actuator including a plurality of lumens, each having a length extending substantially parallel to the elongate interior, each from around 10 to 200 micrometers across and an actuator configured to oscillate the actuator in the actuator housing along the length of the elongate interior with a rate differential between movement in a first …
Powered-Lift Aircraft Category: What Is It?,
2017
Minnesota State University, Mankato
Powered-Lift Aircraft Category: What Is It?, Nihad E. Daidzic
Aviation Department Publications
FAA Safety Seminar (GL1574995) held at Minnesota State University, Mankato at 18:00 CST on Thursday, April 6, 2017.
