Engineering Commons^™

Correlational Study Of Open Circuit Resonant (Sansec) Sensor’S Electric Field Distribution On Lightning Attachment, Kayla M. Farrow, Linda L. Vahala

Electrical & Computer Engineering Faculty Publications

NASA Langley Research Center (LaRC) is conducting research to develop an open circuit SansEC (Sans Electric Connection) sensor to provide lightning strike protection (LSP) in conjunction with damage detection and diagnosis for composite aircraft. SansEC sensors are simplistic devices consisting of an open circuit conductive trace shaped in a planar geometric spiral. The length and width of the conductive trace as well as the gap separation between adjacent turns determines the inductance, resistance and capacitance of the LRC circuit and its associated resonant response. When the sensor is placed on a composite substrate, the electric impedance of the substrate is …

Design Of A Lighter Than Air Vehicle That Achieves Positive Buoyancy In Air Using A Vacuum, Trent T. Metlen

Theses and Dissertations

Three designs for a Lighter Than Air (LTA) structure that achieve positive buoyancy using a vacuum in place of a lifting gas were proposed and evaluated. The ratio of structure weight to the weight of displaced air was termed Weight/Buoyant Force (W/B) where a W/B1 corresponds to positive buoyancy. Two methods of geometrically stiffening a sphere were investigated and their W/B evaluated. A thin shelled sphere of beryllium stiffened with an isogrid of blade type stiffeners using Ultra High Modulus (UHM) carbon epoxy was predicted to give a W/B= 0.79. A geodesic sphere composed of a frame of cylindrical, UHM, …

Ad-Hoc Regional Coverage Constellations Of Cubesats Using Secondary Launches, Guy G. Zohar

Master's Theses

As development of CubeSat based architectures increase, methods of deploying constellations of CubeSats are required to increase functionality of future systems. Given their low cost and quickly increasing launch opportunities, large numbers of CubeSats can easily be developed and deployed in orbit. However, as secondary payloads, CubeSats are severely limited in their options for deployment into appropriate constellation geometries.

This thesis examines the current methods for deploying cubes and proposes new and efficient geometries using secondary launch opportunities. Due to the current deployment hardware architecture, only the use of different launch opportunities, deployment direction, and deployment timing for individual cubes …

International Standardization Compliance In Aviation, Tyler Brogden Spence

Open Access Theses

The commercial aviation industry is global in the sense that passengers travel around the world from destination to destination. It is also global in that the states of the world (countries) regulate the industry domestically and internationally. There is a unique stage where the world comes together to promote aviation, discuss ideas and establish international standards. This stage is the International Civil Aviation Organization (ICAO). The 191 current member states signed treaties acknowledging their commitment to abiding by the standards and practices established by ICAO. No state is 100 percent compliant with international standards, however, and the purpose of this …

Optimizing The Mechanical Characteristics Of Bamboo To Improve The Flexural Behavior For Biocomposite Structural Application, Jay Lopez

Master's Theses

Global awareness and preservation have spurred increasing interest in utilizing environmentally friendly materials for high-performance structural applications. Biocomposites pose an appealing solution to this issue and are characterized by their sustainable lifecycles, biodegradable qualities, light weight, remarkable strength, and exceptional stiffness. Many of these structural qualities are found in applications that exhibit flexural loading conditions, and this study focuses on improving the bending performance of engineered biocomposite structures. The current application of biocomposites is increasing rapidly, so this expanding research explores other natural constituent materials for biocomposite structures under flexural loading.

The renewable material investigated in this study was experimentally …

The Synergistic Integration Of Computational Fluid Dynamics And Experimental Fluid Dynamics For Ground Effect Aerodynamics Studies, Tj Barber, G Doig, C Beves, I Watson, S Diasinos

Aerospace Engineering

This article highlights the ‘synergistic’ use of experimental fluid dynamics (EFD) and computational fluid dynamics (CFD), where the two sets of simulations are performed concurrently and by the same researcher. In particular, examples from the area of ground effect aerodynamics are discussed, where the major facility used was also designed through a combination of CFD and EFD. Three examples are than outlined, to demonstrate the insight that can be obtained from the integration of CFD and EFD studies. The case studies are the study of dimple flow (to enhance aerodynamic performance), the analysis of a Formula-style front wing and wheel, …

Integration, Testing And Validation, Of A Small Hybrid-Electric Remotely-Piloted Aircraft, Joseph K. Ausserer

Theses and Dissertations

Parallel hybrid-electric technology offers a wide variety of new mission capabilities including low-observable loiter operations and increased fuel efficiency for small remotely-piloted aircraft. This research focused on the integration, validation, and testing of a hybrid-electric propulsion system consisting of commercially available components to fabricate a small remotely-piloted aircraft capable of extended low-observable operation. Three novel aspects contributed to the success of the design: optimization of the propulsive components to the integrated system, torque control of the components for additive power, and a one-way bearing/ pulley mechanism (patent pending) mechanically linking the hybrid system components. To the knowledge of the author …

Thermal Stability Characteristics Of Fisher-Tropsch And Hydroprocessed Alternative Aviation Fuels In A Fixed Bed Reactor, Sergio Quintero

Electronic Theses and Dissertations

Growing prices, limited supply, and public concern about greenhouse gases associated with crude-derived jet fuels have led to development of renewable alternatives which must be compatible with the worldwide civilian and military aviation infrastructure, which were designed for operation with Jet-A/JP-8. Any alternative fuel should not have negative effects on the aircraft engines and fuel systems, especially from a thermal stability perspective, since any adverse effect of the physical properties, and chemical composition, including existence of trace elements, of those fuels may only be revealed after extensive operation, resulting in higher life-cycle maintenance and operation costs. This study considered four …

The Allen Telescope Array Search For Electrostatic Discharges On Mars, Marin M. Anderson, Andrew P.V. Siemion, William C. Barott, Geoffery C. Bower, Gregory T. Delory, Imke De Pater, Dan Werthimer

Department of Electrical Engineering and Computer Science - Daytona Beach

The Allen Telescope Array was used to monitor Mars between 2010 March 9 and June 2, over a total of approximately 30 hr, for radio emission indicative of electrostatic discharge. The search was motivated by the report from Ruf et al. of the detection of non-thermal microwave radiation from Mars characterized by peaks in the power spectrum of the kurtosis, or kurtstrum, at 10 Hz, coinciding with a large dust storm event on 2006 June 8. For these observations, we developed a wideband signal processor at the Center for Astronomy Signal Processing and Electronics Research. This 1024 channel spectrometer calculates …

Women In The Aviation Industry, Maureen N. Mutisya

Senior Honors Theses

The Aviation industry has developed extensively since its establishment by the Wright Brothers in 1903. Over time, the highly male-dominated industry experienced significant changes to incorporate female aviators. Determined women initiated this process through participating in the aircraft engineering sector and pursuing careers as pilots. However, these women faced various challenges, which resulted in setbacks to their effective growth in the industry. In fact, vital issues encountered in the past are still present and often overlooked in today’s aviation industry. Therefore, identifying these problems and proposing solutions with effective corrective measures is necessary to increase and motivate female pilots globally.

Modeling And Analysis Of Low Earth Orbit Satellite And Ground Station Data Exchange Topology, Ersin Kocoglu

Mechanical & Aerospace Engineering Theses & Dissertations

In order to utilize space effectively, the primary function of satellite control in orbit around the Earth must be accomplished. This controlling process includes two main segments, ground stations serving as the controller units and orbiting satellites as the units to be controlled. This thesis explores a topological data exchange model that contains one satellite and multiple ground stations. The model is implemented in digital computer software. This model has multiple purposes and can be used to simulate satellite passes over ground stations and can also be used to predict communication time and the amount of transferred data. The model …

Verification Of Kam Theory On Earth Orbiting Satellites, Christian L. Bisher

Theses and Dissertations

This paper uses KAM torus theory and Simplified General Perturbations 4 (SGP4) orbit prediction techniques compiled by Dr. William Wiesel and compares it to Analytical Graphics ® Incorporated (AGI) Satellite Toolkit ® (STK) orbit data. The goal of this paper is to verify KAM torus theory can be used to describe and propagate an Earth satellite orbit with similar accuracy to existing general perturbation techniques. Using SGP4 code including only truncated geopotential effects, KAM torus generating code, and other utilities were used to describe a particular satellite orbit as a torus and then propagate the satellite using traditional and KAM …

The Role Of Education In Small Satellite Programmes, Olaleye Salu

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Olaleye Salu titled "The Role of Education in Small Satellite Programmes" from September 9, 2009.

Satellite Earth Observation And Surveillance Payloads, Rainer Sandau

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint presentation created by Rainer Sandau titled "Satellite Earth observation and surveillance payloads" from April 9, 2009.

(U) Cubesat Experiments (Qb X), Patrick Bournes, Dave Williamson

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Patrick Bournes and Dave Williamson titled "(U) CubeSat Experiments (Qb X)" from April of 2009.

Satellite Reentry Control Via Surface Area Amplification, Salvador Alemán

Theses and Dissertations

This project endeavors to find whether it is feasible to use an increase in surface area as a way of increasing the drag on an orbiting object, thus decreasing its orbital lifetime. The surface area increase can be achieved by an apparatus that deploys a balloon. The balloon will act as a parachute that will decrease the potential energy of the object through atmospheric drag. This is most effective by objects that reach the Low Earth altitudes of less than 500 kilometers, where an object is encountering a firmer atmospheric density. The project is carried out through propagating three different …

An Investigation Into The Feasibility Of Using A Modern Gravity Gradient Instrument For Passive Aircraft Navigation And Terrain Avoidance, Marshall M. Rogers

Theses and Dissertations

Recently, Gravity Gradient Instruments (GGIs) - devices which measure the spatial derivatives of gravity, have improved remarkably due to development of accelerometer technologies. Specialized GGIs are currently flown on aircraft for geological purposes in the mining industries. As such, gravity gradient data is recorded in flight and detailed gradient maps are created after post mission processing. These maps, if stored in a database onboard an aircraft and combined with a GGI, form the basis for a covert navigation system using a map matching process. This system is completely passive and essentially unjammable. To determine feasibility of this method, a GGI …

Selecting And Conserving Lands For Biodiversity: The Role Of Remote Sensing, John Wiens, Robert Sutter, Mark Anderson, Jon Blanchard, Analie Barnett, Naikoa Aguilar-Amuchastegui, Chadwick Avery, Stephen Laine

United States Air Force: Publications

A major focus of conservation is on protecting areas to ensure the persistence of biological diversity. Because such areas may be large, not easily accessible, subject to change, and sensitive to the surrounding landscape, remote sensing can be a valuable tool in establishing and managing protected areas. We describe three case studies to illustrate how remote sensing can contribute to setting priorities for conservation actions, monitoring the status of conservation targets, and evaluating the effectiveness of conservation strategies. In the Connecticut River watershed, remote sensing has been used to assess flood regimes and identify key areas of floodplain forests and …

Volcanic Activity: Processing Of Observation And Remote Sensing Data (Vapor), Mark Wylie

Reports

The World Bank makes a very clear distinction between disasters and natural phenomena. Natural phenomena are events like volcanic eruptions. A disaster only occurs when the ability of the community to cope with natural phenomenon has been surpassed, causing widespread human, material, economic or environmental losses. By these definitions, volcanic eruptions do not have to lead to disasters. On November 13, 1985, the second most deadly eruption of the twentieth century occurred in Colombia. Within a few hours of the eruption of the Nevado del Ruiz volcano, 23,000 people were dead because no infrastructure existed to respond to such an …

Impact Of Phlebotomine Sand Flies On U.S. Military Operations At Tallil Air Base, Iraq: 3. Evaluation Of Surveillance Devices For The Collection Of Adult Sand Flies, Douglas A. Burkett, Ronald Knight, James A. Dennett, Van Sherwood, Edgar Rowton, Russell E. Coleman

United States Air Force: Publications

We evaluated the effectiveness of commercially available light traps and sticky traps baited with chemical light sticks for the collection of phlebotomine sand flies. Evaluations were conducted at Tallil Air Base, Iraq, in 2003. In an initial study, a Centers for Disease Control and Prevention (CDC)-style trap with UV bulb collected significantly more sand flies than did an up-draft CDC trap, a standard down-draft CDC trap (STD-CDC), or a sticky strap with a green chemical light stick. In a subsequent study, we found that the addition of chemical light sticks to sticky traps resulted in a significant increase in the …

Towards Monitoring Galileo: The European Gnss Supervisory Authority In Statu Nascendi = Zur Künftigen Überwachungsagentur Des Galileo Systems, Vers Une Autorité De Surveillance Du Système Galileo, Frans G. Von Der Dunk

Space, Cyber, and Telecommunications Law Program: Faculty Publications

There is little doubt that one of the most interesting and revolutionary, but also complicated and challenging space projects of today is Galileo, Europe’s own full-fledged second-generation navigation satellite system. Developed jointly by the European Union through the Commission and the European Space Agency, Galileo should by the end of the decade have thirty operational satellites in middle-earth-orbits providing timing, positioning and navigation signals across the globe.

From the very beginning Galileo was envisaged in particular by the Commission as a public-private-partnership (PPP). On the one hand, a private concessionaire should operate the system as of full operational capability (originally …

Privatization Of Space Ventures: Proposing A Proven Regulatory Theory For Future Extraterrestral Appropriation, Jonathan Thomas

Brigham Young University International Law & Management Review

No abstract provided.

Overview Of The Stanford Satellite Program, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Overview of the Stanford Satellite Program" from March 4, 2004.

Hands-On Fun & Games In Space Also, On Land, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Hands-On Fun & Games in Space Also, on Land" from January 12, 2004.

Space Adventures By Stanford Students & Mentors, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Space Adventures by Stanford Students & Mentors" from December 10, 2003.

The Conference Proceedings Of The 2003 Air Transport Research Society (Atrs) World Conference, Volume 5, Brent Bowen, Sveinn Gudmundsson, Tae Hoon Oum, Uno Aviation Institute

Faculty Books and Monographs

UNOAI Report 03-9

Nasa - Jpl: Space Adventures By Stanford Students & Mentors, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "NASA - JPL: Space Adventures by Stanford Students & Mentors" from June 25, 2003.

Spacecraft Design & Operations & Other Things, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Spacecraft Design & Operations & Other Things" from April 4, 2003.

Experimental Demonstration Of An Algorithm To Detect The Presence Of A Parasitic Satellite, Vincent J. Dabrowski

Theses and Dissertations

Published reports of microsatellite weapons testing have led to a concern that some of these "parasitic" satellites could be deployed against US satellites to rendezvous dock and then disrupt, degrade disable or destroy the system. An effective detection method is essential. Various sensing solutions were investigated including visual, impact, and dynamic techniques. Dynamic detection, the most effective solution, was further explored. A detection algorithm was constructed and validated on the Air Force Institute of Technology's ground-based satellite simulator, SIMSAT. Results indicate that microsat microsatellites rigidly connected to a satellite can be detected with a series of small identical maneuvers utilizing …

Stanford Classes At Nasa Ames, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "Stanford Classes At NASA Ames" from December 10, 2002.