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Design And Characterization Of A Space Based Chromotomographic Hyperspectral Imaging Experiment, Jason D. Niederhauser 2011 Air Force Institute of Technology

Design And Characterization Of A Space Based Chromotomographic Hyperspectral Imaging Experiment, Jason D. Niederhauser

Theses and Dissertations

This research focuses upon the design, analysis and characterization of several systems related to a spacebased chromotomographic experiment (CTEx), a hyperspectral imager, currently in development at the Air Force Institute of Technology. Three interrelated subject-areas were developed. The initial focal point was a generic, system-level mechanical layout and integration analysis of the space-based instrument. The scope of this work was intended to baseline the space-based system design in order to allow for further trade-space refinement and requirements development. Second, development of an iteration upon the ground-based version of CTEx was accomplished in an effort to support higher-fidelity field data-collection. This …


Operational Characteristics Of A Rotating Detonation Engine Using Hydrogen And Air, Rachel M. Russo 2011 Air Force Institute of Technology

Operational Characteristics Of A Rotating Detonation Engine Using Hydrogen And Air, Rachel M. Russo

Theses and Dissertations

Rotating detonation engines (RDE) are pressure gain combustion engines that have the potential for greater efficiency than traditional, constant pressure, deflagration engines. RDEs are smaller and mechanically simpler than pulsed detonation engines. A small diameter (3 in) engine was successfully run on hydrogen and air. Most of the tests were conducted using air with a slightly lower diluents percentage (77% nitrogen as opposed to 79% nitrogen). These tests provided the foundation for determining the operational space (mass flow rate and equivalence ratio) of the rotating detonation engine. From the tests conducted with the lower diluents air, the appropriate run conditions …


Optical Flow-Based Odometry For Underground Tunnel Exploration, Terra Kier 2011 Air Force Institute of Technology

Optical Flow-Based Odometry For Underground Tunnel Exploration, Terra Kier

Theses and Dissertations

As military operations in degraded or GPS-denied environments continue to increase in frequency and importance, there is an increased necessity to be able to determine precision location within these environments. Furthermore, authorities are finding a record number of tunnels along the U.S.-Mexico border; therefore, underground tunnel characterization is becoming a high priority for U.S. Homeland Security as well. This thesis investigates the performance of a new image registration technique based on a two camera optical- flow configuration using phase correlation techniques. These techniques differ from other image based navigation methods but present a viable alternative increasing autonomy and answering the …


Process For Refining And Validating A Finite Element Model Of An Experimental High-Altitude, Long-Endurance (Hale) Aircraft, Nicholas A. Sinnokrak 2011 Air Force Institute of Technology

Process For Refining And Validating A Finite Element Model Of An Experimental High-Altitude, Long-Endurance (Hale) Aircraft, Nicholas A. Sinnokrak

Theses and Dissertations

The work presented here focuses on finite element (FE) modeling of X-HALE, a test aircraft designed and built by the University of Michigan, in conjunction with the Air Force Institute of Technology (AFIT) and Air Force Research Laboratory (AFRL). This scaled vehicle is representative of high-altitude, long-endurance (HALE) aircraft and was designed to provide controlled aeroelastic and flight data. FE models of portions of the X-HALE wing structure were created and analysis results were compared against two separate laboratory static bending tests conducted on X-HALE wing sections. The process documented here should improve future efforts to refine FE models of …


Effect Of Molecular Film Thickness On Thermal Conduction Across Solid-Film Interfaces, Zhi Liang, Hai-Lung Tsai 2011 Missouri University of Science and Technology

Effect Of Molecular Film Thickness On Thermal Conduction Across Solid-Film Interfaces, Zhi Liang, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Brownian Motion and Aggregation of Particles in Nanofluids Often Lead to the Formation of Solid-Film-Solid Structures. the Molecular Thin Film Confined between Nanoparticles May Have Non-Negligible Effects on Thermal Conduction among Nanoparticles. using Nonequilibrium Molecular Dynamics Simulations, We Study Thermal Conduction Across the Ag Particle-Ar Thin-Film Interface. If the Film Contains Only One Molecular Layer, We Find that the Solid-Film Interfacial Thermal Resistance RSF is About 1 Order of Magnitude Smaller Than the Solid-Liquid (Bulk) Interfacial Thermal Resistance RSL. If There Are Two or More Molecular Layers in the Film, It is Shown that RSF Increases Rapidly toward RSL …


The Effects Of Damage Arrestment Devices In Composite Plate Sandwiches With Fastener Holes, Mark Anderson, Nancy Hung Choy, Lacey Jones, Rita Kourskaya 2011 California Polytechnic State University, San Luis Obispo

The Effects Of Damage Arrestment Devices In Composite Plate Sandwiches With Fastener Holes, Mark Anderson, Nancy Hung Choy, Lacey Jones, Rita Kourskaya

Aerospace Engineering

Composite materials such as a carbon fiber are used in a variety of new technologies including aircraft, spacecraft, and motor vehicles. Carbon fiber has a high strength to weight ratio, a key advantage over other material options. This report discusses the use of composite damage arrestment devices (DADs) in composite sandwich panels with a foam core. There are three different curing cycles tested for the DADs: pressure only, vacuum only, and vacuum with 1000 lbs of pressure. Using a Tetrahedron Heat Press to cure the composite specimen and an Instron Machine to perform tensile testing, data was collected for each …


Composite I-Beam Fabrication And Testing In Response To 14th Annual Sampe Bridge Competition, Kodi Rider, Niño Noel Las Piñas, Hans Mayta 2011 California Polytechnic State University, San Luis Obispo

Composite I-Beam Fabrication And Testing In Response To 14th Annual Sampe Bridge Competition, Kodi Rider, Niño Noel Las Piñas, Hans Mayta

Aerospace Engineering

Composites are a type of material that generally combines two materials yielding mechanical properties that are different than its constituent parts. These constituents are classified as either a fiber or a matrix. The objective of this project is to create a carbon-fiber composite I-beam that meets the specifications of the SAMPE student bridge competition. The I-beam consists of carbon fiber unidirectional and woven laminas, as well as aluminum honeycomb and high density polystyrene foam to stiffen the structure. The bridge contest rules limit the dimensions and weight of the bridge. The cross-section must be within 4 inches x 4 inches …


Thermal Analysis Of The Cubesat Cp3 Satellite, Jonas Friedel, Sean McKibbon 2011 California Polytechnic State University, San Luis Obispo

Thermal Analysis Of The Cubesat Cp3 Satellite, Jonas Friedel, Sean Mckibbon

Aerospace Engineering

Due to inconsistencies found in the on-orbit thermal data from the CubeSat CP3 satellite between 2007 and 2011, further analysis is performed on a larger number of data from August 2010 through April 2011, aiming to find an explanation for the overall increasing measured temperatures and shortening peak periods. Therefore, the satellite power data as well as orbital anomalies are analyzed leading to the conclusion that the satellite was temporarily (January – March 2011) orbiting with significantly increased sun exposure causing the higher temperatures. The shortened temperature peak periods are explained by alternating albedo values as the main influence in …


Determination Of The Surface Boundary Layer Using A Quadrotor, Andrew Haviland 2011 California Polytechnic State University, San Luis Obispo

Determination Of The Surface Boundary Layer Using A Quadrotor, Andrew Haviland

Aerospace Engineering

Wind velocity data was taken by a quadrotor UAV using accelerometers, gyroscope, and a barometer. Data was taken at different altitudes over a single position to determine the boundary layer at the surface of the earth. The data taken was compared to the results from numerical methods to determine if this is a practice application for a quadrotor. A few weeks before the test was set to get underway, the quadrotor suffered a very hard crash while testing the GPS and altitude hold function and wasn’t able to completely recover from it. Theoretical results and experiment proposal are covered. 


Design, Manufacturing And Testing Of An Environmentally-Green Bipropellant Thruster, Alex Bendoyro, Gabriel Sanchez, Erin Stearns, Phillip Takahashi 2011 California Polytechnic State University, San Luis Obispo

Design, Manufacturing And Testing Of An Environmentally-Green Bipropellant Thruster, Alex Bendoyro, Gabriel Sanchez, Erin Stearns, Phillip Takahashi

Aerospace Engineering

This project reviews the design, manufacturing and experimentation process of a green bi-propellant thruster designed to output 5 lbf. The goals were to successfully design, manufacture and test a thruster, while discovering the complications that arise through out the complete design process of a green thruster. The thruster was successfully designed using ideal rocket equations and the design was successfully confirmed using CFD and FEA. Manufacturing of the thruster was fully planned and revealed mild flaws in thruster design. For example some features were not manufacturable to the exact measurements desired. Testing of the engine gave results inconsistent with expected …


Numerical Modeling Of The Cn Spectral Emission Of The Stardust Re-Entry Vehicle, Alexandre Martin, Erin D. Farbar, Iain D. Boyd 2011 University of Kentucky

Numerical Modeling Of The Cn Spectral Emission Of The Stardust Re-Entry Vehicle, Alexandre Martin, Erin D. Farbar, Iain D. Boyd

Mechanical Engineering Faculty Publications

Re-entry vehicles designed for space exploration are usually equipped with thermal protection systems made of ablative material. In order to properly model and predict the aerothermal environment of the vehicle, it is imperative to account for the gases produced by ablation processes. In the case of charring ablators, where an inner resin is pyrolyzed at a relatively low temperature, the composition of the gas expelled into the boundary layer is complex and may lead to thermal chemical reactions that cannot be captured with simple ow chemistry models. In order to obtain better predictions, an appropriate gas ow chemistry model needs …


Design, Fabrication, And Testing Of An Electromagnetic Rail Gun For The Repeated Testing And Simulation Of Orbital Debris Impacts, Jeff Maniglia, Jordan Smiroldo, Alex Westfall, Guy Zohar 2011 California Polytechnic State University, San Luis Obispo

Design, Fabrication, And Testing Of An Electromagnetic Rail Gun For The Repeated Testing And Simulation Of Orbital Debris Impacts, Jeff Maniglia, Jordan Smiroldo, Alex Westfall, Guy Zohar

Aerospace Engineering

An Electromagnetic Railgun (EMRG) was designed, built, and tested, capable of firing a projectile a 1 gram projectile at 650 m/s muzzle velocity. The EMRG utilizes an injector, a high voltage power supply, a capacitor bank, inductors and rails. The injector fires 2300 psig Nitrogen gas into the system to provide an initial velocity. The high voltage power supply charges the capacitor bank. The capacitor bank discharges the electric potential built up through the projectile while inside the rails in order to create the EMRG’s force. The inductors are used to pulse form the capacitor bank in order to get …


An Analysis Of Stabilizing 3u Cubesats Using Gravity Gradient Techniques And A Low Power Reaction Wheel, Erich Bender 2011 California Polytechnic State University, San Luis Obispo

An Analysis Of Stabilizing 3u Cubesats Using Gravity Gradient Techniques And A Low Power Reaction Wheel, Erich Bender

Aerospace Engineering

The purpose of this paper is to determine the feasibility of gravity gradient stabilizing a 3U CubeSat and then using a miniature reaction wheel to further increase stability characteristics. This paper also serves as a guide to understanding and utilizing quaternions in attitude control analysis. The analytical results show that using 33 centimeter booms and 400 gram tip masses, a 3U CubeSat will experience a maximum of 6 degrees of angular displacement in yaw and pitch, and less than .5 degrees of angular displacement in the nadir axis. A .120 kilogram miniature reaction wheel developed by Sinclair Interplanetary was introduced …


Study Of The Effect Of Different Lay-Up Methods On The Composite Mechanical Characteristics, Veronica Cuevas, Walter Ely Salguero 2011 California Polytechnic State University, San Luis Obispo

Study Of The Effect Of Different Lay-Up Methods On The Composite Mechanical Characteristics, Veronica Cuevas, Walter Ely Salguero

Aerospace Engineering

The purpose of this experiment is to investigate and understand composite structures and the effect of different layup methods on the composite structure, particularly a composite I-beam. One must learn the procedure on how to build the composite I-beam and put it together then build the final composite I-beam and enter the I-beam in the 14th Annual Society for the Advancement of Material and Process Engineering (SAMPE) Student Bridge Contest. The competition will be held May 25th, 2011 in Long Beach, CA. The I-beam was entered in the competition and placed 4th out of 5. The …


Electric Aircraft Propulsion Test Rig Design & Fabrication, Ryan Mayer, Brian Kubicki, Bradley Rodriguez, Austin Harris, David Caudle 2011 California Polytechnic State University, San Luis Obispo

Electric Aircraft Propulsion Test Rig Design & Fabrication, Ryan Mayer, Brian Kubicki, Bradley Rodriguez, Austin Harris, David Caudle

Aerospace Engineering

An electric aircraft propulsion test rig was designed and fabricated to predict thrust, torque and battery discharge profiles for an electric aircraft. The original unit was purchased from ElectraFlyer and included the DC brushless motor, carbon fiber propeller, charger, electronic controller and lithium polymer batteries. Various components were constructed and purchased in order to fabricate the optimal test rig apparatus. This apparatus allows for simultaneous measurement of the torque and thrust of the system through the use of a biaxial sensor. The test rig also measures system voltage and current, which allows the user to determine the discharge profile of …


An Investigation Of Dynamic Soaring And Its Applications To The Albatross And Rc Sailplanes, Christopher J. Lee 2011 California Polytechnic State University, San Luis Obispo

An Investigation Of Dynamic Soaring And Its Applications To The Albatross And Rc Sailplanes, Christopher J. Lee

Aerospace Engineering

Dynamic soaring is a technique used by the sea bird the Albatross. This technique allows for the bird to stay in the air for extended periods of time with very little effort. Dynamic soaring utilizes the wind gradient on the surface of the ocean to maintain its airspeed. A similar technique is used by RC glider pilots to achieve high speeds by using the shear wind layer on the leeward side of mountain ridges.


Analysis And Design Of An Affordable High Altitude Rocket System, Brian Cooper 2011 California Polytechnic State University, San Luis Obispo

Analysis And Design Of An Affordable High Altitude Rocket System, Brian Cooper

Aerospace Engineering

This paper discusses the design of the Rarefied High-Altitude Zenith Experimental Rocket (RHAZER) which is launched at an altitude of 35 kilometers from a weather balloon. The weather balloon is capable of carrying up to 2 kilograms of payload to this altitude, and the rocket can carry a payload of approximately 150 grams to an altitude of at least 80 kilometers and be recovered safely after landing. It is designed to be aerodynamically stable at its launch point, while using fins to spin-stabilize before it enters the low-pressure upper atmosphere. This system has been designed to be used as an …


An Analysis Of N-Body Trajectory Propagation, Emerson Frees II 2011 California Polytechnic State University, San Luis Obispo

An Analysis Of N-Body Trajectory Propagation, Emerson Frees Ii

Aerospace Engineering

Trajectories created with n-body orbit models were propagated in geocentric and interplanetary test cases. The n-body models were created in MATLAB® using numerical integration. In the geocentric test case, the n-body codes were compared to a two-body orbit model and to the default HPOP model used in Satellite Tool Kit®. The interplanetary test case compared the n-body model to the HORIZONS ephemeris data from JPL and an equation for ephemeris propagation. Both cases used the same initial positions and velocities and were propagated for the same duration. The results of the analysis showed that while n-body models …


Development And Design Of A Hovering Controller For Operation In A Dynamic Asteroid Environment, Nicholas Georgiades 2011 California Polytechnic State University, San Luis Obispo

Development And Design Of A Hovering Controller For Operation In A Dynamic Asteroid Environment, Nicholas Georgiades

Aerospace Engineering

The project seeks to develop a dynamic model similar to that present near a solar system small body, and to design a controller suggested in other resources that will allow a spacecraft operating in this environment to hover in a fixed location in the relative reference frame of the small body. The paper discusses the derivation of the equations of motion used in the non-linear dynamic model, the design of the controller that will allow the spacecraft to hover, and the development of the control loop that will simulate the spacecraft hovering in the dynamic environment of the asteroid 1999 …


Flexi-Focus Lens: Pdms Variable Focal Length Lens, Patrick Angulo, Alex Doyle, Dylan McDaniel, Michael Olivarez 2011 California Polytechnic State University - San Luis Obispo

Flexi-Focus Lens: Pdms Variable Focal Length Lens, Patrick Angulo, Alex Doyle, Dylan Mcdaniel, Michael Olivarez

Industrial and Manufacturing Engineering

The design of a variable focal length, or flexi-focus, polydimethylsiloxane (PDMS) lens incorporating a light emitting diode (LED) source is intended for future use on board commercial aircraft. Specifically, the design is intended for the Boeing 787 Dreamliner aircraft, serving as a personal reading light for the passengers seated in the cabin. Most current reading lights on board aircraft are rigid, incandescent, and have very limited freedom in terms of adjusting the emitted light. Incandescent lamps are also inefficient with respect to energy consumption and light output as well as a high heat output. In an economy of increasing demand …


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