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Modeling Martian Planetary Entry Descent And Landing Using Monte Carlo Driven Response Surface Methodology, Narcrisha S. Norman 2012 Old Dominion University

Modeling Martian Planetary Entry Descent And Landing Using Monte Carlo Driven Response Surface Methodology, Narcrisha S. Norman

Mechanical & Aerospace Engineering Theses & Dissertations

Response surface methodology (RSM) is a statistical method that explores the relationships between several descriptive variables and one or more response variables. For over sixty years, among other areas, it has been utilized in quality engineering, process engineering, aircraft engineering, economics, chemical engineering, automotive engineering and design/technique optimization. In this dissertation, RSM is utilized to produce regression models that represent the planetary entry, descent and landing (EDL) process. A complete understanding of EDL process is an essential component of any planetary exploration. Research in this area is ongoing and confidence in the ability to explore known celestial bodies is growing. …


Modification And Application Of A Turbulence Response Analysis Method For Flexible Aircraft Configurations, Christie Jeanne Funk 2012 Old Dominion University

Modification And Application Of A Turbulence Response Analysis Method For Flexible Aircraft Configurations, Christie Jeanne Funk

Mechanical & Aerospace Engineering Theses & Dissertations

A software program and associated methodology to study gust loading on aircraft exists for a classification of geometrically simplified flexible configurations. This program consists of a simple aircraft response model with two rigid and three flexible symmetric degrees of freedom and allows for the calculation of various airplane responses due to a discrete one-minus-cosine gust as well as continuous turbulence. Simplifications, assumptions, and opportunities for potential improvements pertaining to the existing software program are first identified, then a revised version of the original software tool is developed with improved methodology to include more complex geometries, additional excitation cases, and output …


Educating Undergraduate Space Science Students With Real Space Missions: Nanosatellite And Nanolab Missions In Kentucky, Robert J. Twiggs 2012 Morehead State University

Educating Undergraduate Space Science Students With Real Space Missions: Nanosatellite And Nanolab Missions In Kentucky, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Professor Bob Twiggs titled "Educating Undergraduate Space Science Students with Real Space Missions: NanoSatellite and NanoLab Missions in Kentucky" from September 27, 2012.


Effect Of Accessory Power Take-Off Variation On A Turbofan Engine Performance, Anis Faidi 2012 Air Force Institute of Technology

Effect Of Accessory Power Take-Off Variation On A Turbofan Engine Performance, Anis Faidi

Theses and Dissertations

Engine fuel efficiency of aerospace vehicles can be reached by different techniques. One way to do that is to reduce aircraft subsystems power supply effects on the engine performance. Previous research work has showed that extracting bleed air from the high pressure compressor exit is more efficient than extracting the equivalent amount of energy from the low pressure spool shaft. A high bypass turbofan engine was modeled using the Numerical Propulsion System Simulation (NPSS). The baseline engine performance was evaluated at different flight conditions of Mach number and altitude. To better understand the effect of air bleed take-off and shaft …


Fundamental Sizing Implications Of Constant Or Increasing Weight Aircraft, Robert A. McDonald 2012 California Polytechnic State University - San Luis Obispo

Fundamental Sizing Implications Of Constant Or Increasing Weight Aircraft, Robert A. Mcdonald

Aerospace Engineering

As the energy storage capabilities of batteries and fuel cells advance, these technologies are increasingly being considered for aircraft primary propulsion. In addition to other fundamental differences from conventional systems, these concepts may have constant or even increasing mass throughout the mission. In this paper, the implications of constant or increasing mass on aircraft sizing are considered with the aim of generating insight for the design of these systems.


Scaling Study Of Wave Rotor Turbo-Normalization Of A Small Internal Combustion Engine, Brandon D. Smith 2012 Air Force Institute of Technology

Scaling Study Of Wave Rotor Turbo-Normalization Of A Small Internal Combustion Engine, Brandon D. Smith

Theses and Dissertations

One issue facing small Remotely Piloted Aircraft engines is their ability to maintain performance at altitude. Since many of these aircraft use commercial off the shelf engines originally designed for radio controlled aircraft and lawn care implements, the reduced pressure environment significantly degrades the operability of the engine as the altitude increases. An option to overcome this difficulty is to supercharge the system; however most superchargers are designed for larger, typically automotive, engines. As a supercharger's size is decreased, there are large efficiency losses. Therefore, there is a need to accomplish this function on a smaller scale without. One option …


Operationally Responsive Spacecraft Using Electric Propulsion, Thomas C. Co 2012 Air Force Institute of Technology

Operationally Responsive Spacecraft Using Electric Propulsion, Thomas C. Co

Theses and Dissertations

A desirable space asset is responsive and flexible to mission requirements, low-cost, and easy to acquire. Highly-efficient electric thrusters have been considered a viable technology to provide these characteristics; however, it has been plagued by limitations and challenges such that operational implementation has been severely limited. The technology is constantly improving, but even with current electric propulsion, a spacecraft is capable of maneuvering consistently and repeatedly in low-Earth orbit to provide a responsive and flexible system. This research develops the necessary algorithm and tools to demonstrate that EP systems can maneuver significantly in a timely fashion to overfly any target …


Novel Discretization Schemes For The Numerical Simulation Of Membrane Dynamics, Kyle F. Kolsti 2012 Air Force Institute of Technology

Novel Discretization Schemes For The Numerical Simulation Of Membrane Dynamics, Kyle F. Kolsti

Theses and Dissertations

Motivated by the demands of simulating flapping wings of Micro Air Vehicles, novel numerical methods were developed and evaluated for the dynamic simulation of membranes. For linear membranes, a mixed-form time-continuous Galerkin method was employed using trilinear space-time elements, and the entire space-time domain was discretized and solved simultaneously. For geometrically nonlinear membranes, the model incorporated two new schemes that were independently developed and evaluated. Time marching was performed using quintic Hermite polynomials uniquely determined by end-point jerk constraints. The single-step, implicit scheme was significantly more accurate than the most common Newmark schemes. For a simple harmonic oscillator, the scheme …


Investigation Into Suitability Of Geopolymers (Illite & Metakaolin) For The Space Environment, Brandon T. Cesul 2012 Air Force Institute of Technology

Investigation Into Suitability Of Geopolymers (Illite & Metakaolin) For The Space Environment, Brandon T. Cesul

Theses and Dissertations

Suitability of non-organic polymers for space application is studied. Materials included are illite and metakaolin. Bulk material suitability was investigated for exposure to ultraviolet radiation, atomic oxygen, and high energy charged particles. Outgassing phenomenon of the materials was studied. Curing shrinkage reduction techniques were identified as well.


A (Declassified) History Of Military Drones, Stephen Rayleigh 2012 Embry-Riddle Aeronautical University

A (Declassified) History Of Military Drones, Stephen Rayleigh

ERAU Prescott Aviation History Program

Unmanned Aerial Vehicles or drones, are said to be the newest technology of contemporary warfare, but the military's use of drones spans the last 100 years. Hear the riveting story of the numerous secret UAV programs around the world, starting with the Sperry Aerial Torpedo Project in 1918 (consulted by Orville Wright), the German cruise missile program, American remote controlled bombers in WWII, the Firebee recon drone used in Vietnam, Israel's highly successful UAV program, and finally the coming of age of UAV's in Operation Desert Storm.


The Characterization Of Material Properties And Structural Dynamics Of The Manduca Sexta Forewing For Application To Flapping Wing Micro Air Vehicle Design, Ryan P. O'Hara 2012 Air Force Institute of Technology

The Characterization Of Material Properties And Structural Dynamics Of The Manduca Sexta Forewing For Application To Flapping Wing Micro Air Vehicle Design, Ryan P. O'Hara

Theses and Dissertations

The Manduca Sexta species of moth serves as a source of biological inspiration for the future of micro air vehicle flapping flight. The ability of this species to hover in flapping flight has warranted investigation into the critical material, structural, and geometric properties of the forewing of this biological specimen. A rigorous morphological study of the Manduca Sexta forewing was conducted to characterize the physical and material properties of the biological forewing for the purpose of developing an advanced parametric three dimensional model finite element analysis (FEA) model. This FEA model was tuned to match the experimentally determined structural dynamics …


Novel Crankshaft Mechanism And Regenerative Braking System To Improve The Fuel Economy Of Light Duty Vehicles And Passenger Cars, Alberto A. Boretti, Joseph Scalzo 2012 Missouri University of Science and Technology

Novel Crankshaft Mechanism And Regenerative Braking System To Improve The Fuel Economy Of Light Duty Vehicles And Passenger Cars, Alberto A. Boretti, Joseph Scalzo

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Improvements of vehicle fuel economy may be achieved by the introduction of advanced internal combustion engines (ICE) improving the fuel conversion efficiency of the engine and of advanced power trains (PWT) reducing the amount of fuel energy needed to power the vehicle. the paper presents a novel design of a variable compression ratio advanced spark ignition engine that also permits an expansion ratio that may differ from the compression ratio hence generating an Atkinson cycle effect. the stroke ratio and the ratio of maximum to minimum in-cylinder volumes may change with load and speed to provide the best fuel conversion …


Characteristics, Causes, And Evaluation Of Helicopter Particulate Obstruction, Michael P. Sullivan 2012 Air Force Institute of Technology

Characteristics, Causes, And Evaluation Of Helicopter Particulate Obstruction, Michael P. Sullivan

Theses and Dissertations

A comprehensive approach to evaluation of rotorcraft brownout under degraded visual environmental conditions is presented. The results of a literature search covering the current state of brownout research are summarized. The brownout dust cloud generated by modern rotorcraft is analyzed and characterized using photographic and video data, coupled with examination of previous computer modeling techniques. A modeling analysis is performed in order to relate aircraft design and operating parameters to brownout dust cloud size is performed. The effect of vorticity in brownout dust cloud rollup is included. An augmented rating scale for pilot assessment is proposed for operational use, and …


Cfd Transient Simulation Of An Isolator Shock Train In A Scramjet Engine, Troy C. Hoeger 2012 Air Force Institute of Technology

Cfd Transient Simulation Of An Isolator Shock Train In A Scramjet Engine, Troy C. Hoeger

Theses and Dissertations

For hypersonic flight, the scramjet engine uses an isolator to contain the pre-combustion shock train formed by the pressure difference between the inlet and the combustion chamber. If this shock train were to reach the inlet, it would cause an engine unstart, disrupting the flow through the engine and leading to a loss of thrust and potential loss of the vehicle. Prior to this work, a Computational Fluid Dynamics (CFD) simulation of the isolator was needed for simulating and characterizing the isolator flow and for finding the relationship between back pressure and changes in the location of the leading edge …


Proposed Msu Matchbooksat For Iss Launch 2014, Robert J. Twiggs 2012 Morehead State University

Proposed Msu Matchbooksat For Iss Launch 2014, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Professor Bob Twiggs titled "Proposed MSU MatchBookSat for ISS Launch 2014" from September 6, 2012.


Performance Effects Of Damage Arrestment Devices On Sandwich Composite Beams Under Monotonic Loading, Yvette Vanessa Wood 2012 California Polytechnic State University, San Luis Obispo

Performance Effects Of Damage Arrestment Devices On Sandwich Composite Beams Under Monotonic Loading, Yvette Vanessa Wood

Aerospace Engineering

Face-core delamination has become a subject matter in the Aerospace industry, as it can lead to early failure. In this study, sandwich composite beams are tested initially with no delamination to obtain the ultimate strength. A second case of delamination in the center of the beam in initialized to verify a decrease in ultimate strength. This experiment investigates the performance effects of the addition of Damage Arrestment Devices (DADs), in composite sandwich beams. The performance criterion is measured by strength in flexural loading test. The objective of this project is to verify an increase in the strength and performance with …


Jet Engine Thrust Ratings, Nihad E. Daidzic 2012 Minnesota State University, Mankato

Jet Engine Thrust Ratings, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.


Optimal Slewing Of A Constrained Telescope Using Seventh Order Polynomial Input Torques, Julia K. Bush 2012 California Polytechnic State University, San Luis Obispo

Optimal Slewing Of A Constrained Telescope Using Seventh Order Polynomial Input Torques, Julia K. Bush

Master's Theses

Two-axis gimbals are frequently used to point cameras and telescopes at various points of interest for surveillance, science, and art. The rotation of a two-axis gimbal system is governed by nonlinear angular momentum equations of motion. This paper presents a method for slewing a telescope in space with a gimbaled sensor attached to a nominally non-rotating spacecraft using two seventh order polynomial input functions to characterize torques. To accomplish this task, picking the optimal coefficients of the seventh order polynomial was necessary. It was also desired to use constraint equations to limit the excursion, angular velocity, angular acceleration, and jerk …


An Alternative Dual-Launch Architecture For A Crewed Asteroid Mission, Steven M. Korn 2012 California Polytechnic State University, San Luis Obispo

An Alternative Dual-Launch Architecture For A Crewed Asteroid Mission, Steven M. Korn

Master's Theses

This thesis is a feasibility study for a crewed mission to a Near Earth Asteroid (NEA). An alternate dual-launch architecture is proposed and analyzed against a more established architecture. Instead of a rendezvous in a low-Earth parking orbit, the new architecture performs the rendezvous while the two spacecraft are on an Earth-escape trajectory to the destination NEA. After selecting a target asteroid, 2000 SG344, each architecture will have its best mission compared to the best mission of the other architecture.

Using the new architecture, a mission is created to the chosen NEA, 2000 SG344. A back-up Orion MPCV and a …


The New Bicycle Model: Introducing Software Considerations Early Into The Systems Engineering Design And Integration Process, Nathaniel Dinglasan Angat 2012 California Polytechnic State University, San Luis Obispo

The New Bicycle Model: Introducing Software Considerations Early Into The Systems Engineering Design And Integration Process, Nathaniel Dinglasan Angat

Master's Theses

Lockheed Martin Space Systems Company, Sunnyvale, California is in the business of designing and engineering satellites for commercial and government customers. This task is by no means a trivial endeavor but Lockheed MartinSunnyvale has many decades of experience in Systems Engineering. Training in systems engineering is a long process whose training tools must be kept up-to-date and appropriate as new advances in technology evolve along-side with the processes that develop these ever-evolving solutions. For many years new systems engineers have been introduced to the Bicycle Model as a paradigm for designing and developing complex systems that are composed of diverse …


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