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Air Force Institute of Technology

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Value Focused Thinking Approach Using Multivariate Validation For Junior Enlisted Performance Reporting In The United States Air Force, Christopher M. Jones Mar 2014

Value Focused Thinking Approach Using Multivariate Validation For Junior Enlisted Performance Reporting In The United States Air Force, Christopher M. Jones

Theses and Dissertations

From United States Air Force (USAF) doctrine, Air Force Instruction 1-1 lists three purposes for the USAF Enlisted Evaluation System. The first purpose is to provide feedback to individuals on how well they are meeting expectations. The second purpose is to provide a cumulative record of performance and potential based on observations. The third purpose is to identify the best qualified personnel. However, current Air Force leadership has expressed a need to revamp the enlisted appraisal process, requesting consistency in identifying the best performers, reduction in ratings inflation, and better delineation between ?near peer? performers. This research proposes utilizing Value-Focused …

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A Heuristic Approach To The Theater Distribution Problem, Emily K. Power Mar 2014

A Heuristic Approach To The Theater Distribution Problem, Emily K. Power

Theses and Dissertations

Analysts at USTRANSCOM are tasked with providing vehicle mixtures that will support the distribution of requirements as provided in the form of TPFDD. An integer programming model exists to search for optimal solutions to these problems, but it is fairly time consuming, and produces only one of potentially several good quality solutions. This research constructs a number of heuristic approaches to solving the TDP. Two distinct shipping methods are examined and applied through both constructive and probabilistic vehicle assignment processes. Multistart metaheuristic approaches are designed and used in conjunction with the constructive and probabilistic approaches. Random TPFDDs of size 20, …

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Simulating F-22 Heavy Maintenance And Modifications Workforce Multi-Skilling, Wesley A. Sheppard Jr. Mar 2014

Simulating F-22 Heavy Maintenance And Modifications Workforce Multi-Skilling, Wesley A. Sheppard Jr.

Theses and Dissertations

The Air Force faces significant fiscal challenges in the coming years. The aircraft maintenance depot activities at Ogden ALC, Oklahoma City ALC and Warner-Robins ALC face complex operating environments due to the diversity of aircraft or mission design series (MDS) maintained by each depot and the variability of maintenance requirements for each MDS. Further complicating their operations is the variability of maintenance actions required from one aircraft to another within each MDS and a highly specialized workforce that has inherent inflexibility to compensate for the workload variability. Air Force Materiel Command is reviewing maintenance personnel multi-skilling as a method to …

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Optimizing Air Force Depot Programming To Maximize Operational Capability, James D. Rhoads Mar 2014

Optimizing Air Force Depot Programming To Maximize Operational Capability, James D. Rhoads

Theses and Dissertations

The Air Force wants to improve the link between resources and weapons system readiness by reducing costs, improving risk-based decision making, and balancing costs with performance. With that in mind, RAND Project Air Force developed a linear programming model linking Depot Purchased Equipment Maintenance to operational capability. This thesis examined that model, provided an alternate model, and then developed a new model that determined the minimum cost necessary to maintain the force structure. The utility of using the models using Weapon System Sustainment (WSS) and additional sources of data for aircraft and engine inventories was evaluated and critiqued. While every …

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Automatic Target Recognition Using Nonlinear Autoregressive Neural Networks, Marc R. Ward Mar 2014

Automatic Target Recognition Using Nonlinear Autoregressive Neural Networks, Marc R. Ward

Theses and Dissertations

Accurate combat identification is critical to military interactions. Laser radar for vehicle identification is a rapidly developing field that could possibly assist in combat identification by providing information about operating characteristics of a particular vehicle based on measured vibrations. This research focuses on simulated laser radar data collected from mounted vibrometers on idling vehicles. An approach to identify vehicles using nonlinear autoregressive neural networks for classification is developed and employed. The resulting algorithm combines the trained neural networks across three dimensions of vibration readings. This method offers improved performance over literature in successfully identifying a vehicle through vibration measurements alone.

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Analysis Of A Scada System Anomaly Detection Model Based On Information Entropy, Jesse G. Wales Mar 2014

Analysis Of A Scada System Anomaly Detection Model Based On Information Entropy, Jesse G. Wales

Theses and Dissertations

SCADA (supervisory control and data acquisition) systems monitor and control many different types of critical infrastructure such as power, water, transportation, and pipelines. These once isolated systems are increasingly being connected to the internet to improve operations, which creates vulnerabilities to attacks. A SCADA operator receives automated alarms concerning system components operating out of normal thresholds. These alarms are susceptible to manipulation by an attacker. This research uses information theory to build an anomaly detection model that quantifies the uncertainty of the system based on alarm message frequency. Several attack scenarios are statistically analyzed for their significance including someone injecting …

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Enhanced Vehicle Beddown Approximations For The Improved Theater Distribution Model, Jonathan D. White Mar 2014

Enhanced Vehicle Beddown Approximations For The Improved Theater Distribution Model, Jonathan D. White

Theses and Dissertations

Gathering insight into the theater distribution process can be a complex task, especially when estimating potential beddown solutions. Coming up with a low cost feasible mixture of cargo vehicles that will support distribution of military personnel and goods within theater is currently a high priority for force flow analysts at USTRANSCOM. In the past, analysts used a trial and error simulation process that was iterative and time consuming. Recent research has produced the Improved Theater Distribution Model (ITDM), which presents a less time consuming, more precise method to estimate beddown allocations. Improving on this research, two linear programming methods were …

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A Methodology For Measuring Resilience In A Satellite-Based Communication Network, Jonathan S. Turner Mar 2014

A Methodology For Measuring Resilience In A Satellite-Based Communication Network, Jonathan S. Turner

Theses and Dissertations

According to Presidential Policy Directive 21, increasing resilience of critical infrastructures is not only desired, but United States policy. Communications infrastructures are one such critical infrastructure. The purpose of this research is to develop a methodology for measuring resilience in satellite communication systems for use as a key criterion in the selection and acquisition of new satellite architectures, in accordance with the National Security Space Strategy. The base methodology utilized in this thesis is Extreme Event Modeling implemented through the use of Bi-Level Programming with monotonically nonlinear continuous and mixed integer variables. This model differs from previous efforts applied to …

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Strategic Positioning Of United States Air Force Civil Engineer Contingency Equipment Within The Supply Chain, Scott D. Adamson Mar 2014

Strategic Positioning Of United States Air Force Civil Engineer Contingency Equipment Within The Supply Chain, Scott D. Adamson

Theses and Dissertations

The consolidation and forward positioning of critical inventories often provides substantial benefits over a geographically dispersed posture. Such benefits include, but are not limited to: increased inventory visibility, reduced transportation costs, and fewer manpower requirements. Presently, the United States Air Force (USAF) Civil Engineer (CE) community maintains a disseminated posture of equipment Unit Type Codes (UTCs), which regularly experiences inconsistencies in handling, tracking, and capability reporting. Provided the aforementioned discrepancies, this research effort examines several aspects surrounding the decision to potentially centralize critical CE inventories to either one or two locations. Specifically, the areas of cost, risk, and manpower are …

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A Survey And Analysis Of Aircraft Maintenance Metrics: A Balanced Scorecard Approach, Adrienne L. Stahl Mar 2014

A Survey And Analysis Of Aircraft Maintenance Metrics: A Balanced Scorecard Approach, Adrienne L. Stahl

Theses and Dissertations

Performance metrics have helped to sustain the Air Force, improve processes, and guided decisions makers through decades of challenges and change. The Air Force continues to change as it faces the challenges of an aging fleet coupled with the tightest budget constraints of modern times. The current metrics employed by the United States Air Force Aircraft Maintenance community have gone largely unchanged over decades despite a host of force altering events. The focus of this research is to evaluate current maintenance metrics and assess the utility of the Balanced Scorecard framework for use in a Maintenance Group. The researcher utilizes …

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Accounting For Mass Transfer Kinetics When Modeling The Impact Of Low Permeability Layers In A Groundwater Source Zone On Dissolved Contaminant Fate And Transport, James M. Bell Mar 2014

Accounting For Mass Transfer Kinetics When Modeling The Impact Of Low Permeability Layers In A Groundwater Source Zone On Dissolved Contaminant Fate And Transport, James M. Bell

Theses and Dissertations

In this study, the subsurface storage and transport of a Dense Non-Aqueous Phase Liquid (DNAPL) was studied using a numerical model. Recent studies have found evidence that cracks can exist in low permeability layers within aquifers, and that a significant mass of DNAPL can be stored within those cracks. In this research, we simulate the effect of DNAPL in the low permeability cracks on contaminant plume evolution and persistence. A key parameter governing fate is the rate of DNAPL dissolution. In this study, we model the dissolution rate as both a constant and as a function of time, using parameters …

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A Change Management Approach To Enhance Facility Maintenance Programs, Stanton P. Brown Mar 2014

A Change Management Approach To Enhance Facility Maintenance Programs, Stanton P. Brown

Theses and Dissertations

A recent study assigned a grade of D+ on the nation's public infrastructure. Because of this poor asset condition, many organizations tend to respond to maintenance in a reactive mode; however, relying on corrective maintenance leads to increased maintenance costs due to unplanned downtime, increased labor costs, and inefficient use of personnel. To address this situation, asset management (AM) principles should be employed to transition organizations towards a proactive maintenance program. Unfortunately, it has been shown that two-thirds of the organizations failed to implement general change efforts. Therefore, an organizational change management framework should be followed to implement a change …

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A Macro-Stochastic Approach To Improved Cost Estimation For Defense Acquisition Programs, Allen J. Deneve Mar 2014

A Macro-Stochastic Approach To Improved Cost Estimation For Defense Acquisition Programs, Allen J. Deneve

Theses and Dissertations

Space is becoming increasingly congested as more objects are launched into orbit. The potential for a collision on orbit increases each time a new object enters space. This thesis presents a methodology to determine an optimal direction to maneuver a satellite that may be involved in a potential collision. The author presents a paradigm to determine the optimal direction of maneuver to achieve the lowest probability of collision, and examines how different magnitudes of a maneuver will affect the probability of collision. The methodology shows that if a satellite maneuvers in the optimal direction at any time during the orbit, …

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Ultraviolet Light Emitting Diode Use In Advanced Oxidation Processes, Kelsey L. Duckworth Mar 2014

Ultraviolet Light Emitting Diode Use In Advanced Oxidation Processes, Kelsey L. Duckworth

Theses and Dissertations

Cleanup from a hazardous chemical release can result in large volumes of water containing hazardous materials, such as organophosphates. Unfortunately, this water cannot be treated in a municipal wastewater treatment plant without adversely affecting the performance of the plant. A known method for pretreating this water to prepare it for processing in a traditional treatment plant includes the addition of hydrogen peroxide, followed by ultraviolet (UV) light exposure to form reactive hydroxyl radicals which oxidize the chemical. Light emitting diodes (LEDs) are explored as a UV source as they are durable; compact; can be powered by low voltage, direct current …

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Artificial Neural Network Prediction Of Chemical-Disease Relationships Using Readily Available Chemical Properties, Edward J. Brouch Mar 2014

Artificial Neural Network Prediction Of Chemical-Disease Relationships Using Readily Available Chemical Properties, Edward J. Brouch

Theses and Dissertations

The natural environment is burdened with a broad range of toxic chemicals, and there is a need to develop a tool that can accelerate the pace at which we learn how chemicals impact disease. This work developed an artificial neural network (ANN) based model that constructed chemical-disease relationships for chemicals found in the Comparative Toxicogenomics Database. A new chemical classification system, based on the molecular weight, hydrogen donors, and hydrogen acceptors, was created to identify chemicals with a unique number that is directly related to these structural properties of the chemical. Diseases were grouped into 27 categories and the chemical-disease …

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Interface Evaluation For Open System Architectures, Joshua A. Burger Mar 2014

Interface Evaluation For Open System Architectures, Joshua A. Burger

Theses and Dissertations

This research develops a deterministic interface evaluation framework (IEF) in support of the principles identified in the Modular Open Systems Approach (MOSA). Interface evaluation in weapon system development requires a Decision Analysis (DA) method capable of handling a continuously growing alternative set and functioning with limited availability of senior decision makers. Value Focused Thinking (VFT) is selected as the best method for addressing the parameters of the framework. Inputs from the Medium Altitude Unmanned Aircraft System program office are used. An initial value threshold is established to guide open interface decisions, based on assessments of 15 historical decision scenarios. Open …

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Cloud Computing Implementation Organizational Success In The Department Of Defense, Corey J. Perkins Mar 2014

Cloud Computing Implementation Organizational Success In The Department Of Defense, Corey J. Perkins

Theses and Dissertations

The DoD tends to implement user based IT systems without quantifying whether those systems would be properly utilized by the target populous. Focus is generally emphasized on mission enhancement rather than looking at how or if it will be utilized by organizations. There would appear to be no reason for cloud computing to be implemented with the same disregard for acceptance and success. The day of large amounts of data is here and needs to converge with what this thesis investigates, the factors that positively influence organization acceptance and success of cloud computing specifically in the DoD so that is …

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An Analysis Of Stability Properties In Earned Value Management’S Cost Performance Index And Earned Schedule’S Schedule Performance Index, Jacob L. Petter Mar 2014

An Analysis Of Stability Properties In Earned Value Management’S Cost Performance Index And Earned Schedule’S Schedule Performance Index, Jacob L. Petter

Theses and Dissertations

The concept of a Cost Performance Index (CPI) stability rule originated with the seminal article from Christensen and Payne in 1992 and has become routinely cited by subsequent academic literature and EVM authors. A literature review reveals that the definition of what constitutes stability has morphed over time, with three separate definitions of stability permeating the literature. Additionally, while the original Christensen research found the cumulative CPI to be stable in 86% of DoD contracts (from 155 analyzed) at the 20 percent completion point, more recent research from Henderson and Zwikael (2008) questioned the generalizability of these findings. This research …

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Modeling The Effects Of Ultraviolet (Uv) Light Emitting Diode (Led) Use In The Advanced Oxidation Process (Aop), John P. Richwine Mar 2014

Modeling The Effects Of Ultraviolet (Uv) Light Emitting Diode (Led) Use In The Advanced Oxidation Process (Aop), John P. Richwine

Theses and Dissertations

The United States Environmental Protection Agency (EPA) is concerned with both accidental and intentional releases of chemicals into waste streams. Certain chemicals may be detrimental to the effectiveness of municipal wastewater treatment plants. This can lead to reduced capability or costly damage to the plant. An Advanced Oxidation Process (AOP) is one method to pre-treat waste streams. This method uses ultraviolet (UV) energy and hydrogen peroxide to create hydroxyl radicals that can neutralize harmful chemicals. Recent advancements in Ultra Violet Light Emitting Diodes (UV LEDs) are making it possible to use this energy source instead of traditional UV energy sources. …

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Development And Characterization Of A High Speed Mid-Ir Tunable Diode Laser Absorption Spectrometer For Co And Co2 Detection In Detonation Events, Stephen D. Wakefield Mar 2014

Development And Characterization Of A High Speed Mid-Ir Tunable Diode Laser Absorption Spectrometer For Co And Co2 Detection In Detonation Events, Stephen D. Wakefield

Theses and Dissertations

A tunable diode laser absorption spectroscopy system, capable of collecting data at a 10 kHz repetition rate near 4.5 microns. This system was made feasible in recent years due to the development of quantum cascade lasers active in the 4.5 microns region of the spectrum. Reaching into the mid-IR region of the electromagnetic spectrum allowed for an analysis of the fundamental absorption bands for both CO and CO2. The spectral absorption was measured for ethylene, methane, ethane, and propane across a variety of equivalence ratios, at various heights above a Hencken Burner surface. For each fuel, the concentration …

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Improving The Enterprise Requirements And Acquisition Model's Development Test And Evaluation Process Fidelity, Jason W. Sutherlin Mar 2014

Improving The Enterprise Requirements And Acquisition Model's Development Test And Evaluation Process Fidelity, Jason W. Sutherlin

Theses and Dissertations

Shrinking budgets and dynamic military conflicts have driven Department of Defense (DoD) leadership to reform how the military acquires weapon systems with the goal of decreasing program schedules and costs, while maximizing performance. With fifty years of reform, the DoD has been unable to adequately control program schedule objectives. Previous research attempted to support acquisition reforms through modeling and simulation. The Enterprise Requirements and Acquisition Model (ERAM) captures a program's progression through the Defense Acquisition Management System to gain insight into significant delays that impact program schedule and probability of completion. A past unexpected result included the insignificant impact that …

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Integration, Testing, And Analysis Of Multispectral Imager On Small Unmanned Aerial System For Skin Detection, Stephen R. Sweetnich Mar 2014

Integration, Testing, And Analysis Of Multispectral Imager On Small Unmanned Aerial System For Skin Detection, Stephen R. Sweetnich

Theses and Dissertations

Small Unmanned Aerial Systems (SUAS) have been utilized by the military, geological researchers, and first responders, to provide information about the environment in real time. Hyperspectral Imagery (HSI) provides high resolution data in the spatial and spectral dimension; all objects, including skin have unique spectral signatures. However, little research has been done to integrate HSI into SUAS due to their cost and form factor. Multispectral Imagery (MSI) has proven capable of dismount detection with several distinct wavelengths. This research proposes a spectral imaging system that can detect dismounts on SUAS. Also, factors that pertain to accurate dismount detection with an …

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An Analysis Of Eye Movements With Helmet Mounted Displays, Kalyn A. Tung Mar 2014

An Analysis Of Eye Movements With Helmet Mounted Displays, Kalyn A. Tung

Theses and Dissertations

Helmet or Head-Mounted Displays (HMD) applications have expanded to include a range from advanced military cockpits to consumer glasses. However, users have documented loss of legibility while undergoing vibration. Recent research indicates that undesirable eye movement is related to the vibration frequency a user experiences. In vibrating environments, two competing eye reflexes likely contribute to eye movements. The Vestibulo-ocular Reflex responds to motion sensed in the otoliths while the pursuit reflex is driven by the visual system to maintain the desired image on the fovea. This study attempts to isolate undesirable eye motions that occur while using a HMD by …

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Detection And Prevention Of Android Malware Attempting To Root The Device, Justin R. Ball Mar 2014

Detection And Prevention Of Android Malware Attempting To Root The Device, Justin R. Ball

Theses and Dissertations

Every year, malefactors continue to target the Android operating system. Malware which root the device pose the greatest threat to users. The attacker could steal stored passwords and contact lists or gain remote control of the phone. Android users require a system to detect the operation of malware trying to root the phone. This research aims to detect the Exploid, RageAgainstTheCage, and Gingerbreak exploits on Android operating systems. Reverse-engineering 21 malware samples lead to the discovery of two critical paths in the Android Linux kernel, wherein attackers can use malware to root the system. By placing sensors inside the critical …

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Thermal And Melt Wear Characterization Of Materials In Sliding Contact At High Speed Energy Sink, Christopher J. Alban Mar 2014

Thermal And Melt Wear Characterization Of Materials In Sliding Contact At High Speed Energy Sink, Christopher J. Alban

Theses and Dissertations

The Holloman High Speed Test Track is used to evaluate hypersonic aircraft materiel in a near-operational environment. The four-stage pusher rocket sled is capable of accelerating a test apparatus to hypersonic speeds in a matter of seconds. The sled must contend with tremendous thermal, mechanical, and aerodynamic loading during each run. The effects of the combination of forces acting on the sled are most acute at the interface between the rail and the wraparound slipper that holds the sled to the rail. Frictional heating due to sliding contact between the slipper and the rail coupled with mechanical wear can lead …

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Liquid Spray Characterization In Flow Fields With Centripetal Acceleration, Andrew J. Brinker Mar 2014

Liquid Spray Characterization In Flow Fields With Centripetal Acceleration, Andrew J. Brinker

Theses and Dissertations

Performing combustion in the circumferential direction has a significant potential payoff in terms of saving engine length and subsequently weight. What is not understood is the flame dynamics for a liquid fuel when sprayed into a combustor with centripetal acceleration. This investigation used phase Doppler anemometry (PDA) to characterize a nonreacting liquid spray exiting from a nozzle into a circular cavity with centripetal acceleration. The two-component velocity and size of the droplets in the cavity are measured as a function of centripetal acceleration of the air in the cavity. It was found that the droplets are accelerated by the swirling …

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Design And Analysis Of An Attitude Determination And Control Subsystem (Adcs) For Afit's 6u Standard Bus, Erin R. Dannemeyer Mar 2014

Design And Analysis Of An Attitude Determination And Control Subsystem (Adcs) For Afit's 6u Standard Bus, Erin R. Dannemeyer

Theses and Dissertations

The design and testing of AFIT's 6U Attitude Determination and Control Subsystem (ADCS) are explored to establish 3-axis attitude control. The development of AFIT's 6U CubeSat standard bus is an on-going research effort designed to create in-house CubeSat bus components and software. The 6U chassis measures approximately 11 x 24 x 37 cm3 and can have a mass up to 12 kg. The larger bus size (as compared to the more common 3U CubeSat) allows for increased power capabilities and potential to host multiple or larger payloads. Individual ADCS hardware components were either commercially purchased or built in-house and …

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Applying Kam Theory To Highly Eccentric Orbits, Adam B. Dunk Mar 2014

Applying Kam Theory To Highly Eccentric Orbits, Adam B. Dunk

Theses and Dissertations

This research applies KAM theory to highly eccentric orbits for earth orbiting satellites by using spectral methods to find the three basis frequencies resulting from earth's geopotential. Once a torus is created from these frequencies, its dynamics data can be compared to the position data of an integrated data set over multiple orbit types, specifically, orbits with varying eccentricity. The analysis shows that many eccentric orbits are actually KAM tori when the only perturbation is the earth's geopotential. The residuals agree to 10s of meters in most cases. This research also outlines many of the limitations of the current method …

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Thermal Characterization Of The Air Force Institute Of Technology Solar Simulation Thermal Vacuum Chamber, Daniel M. Hatzung Mar 2014

Thermal Characterization Of The Air Force Institute Of Technology Solar Simulation Thermal Vacuum Chamber, Daniel M. Hatzung

Theses and Dissertations

Although predictive thermal modeling on CubeSats has previously been accomplished, a method to validate these predictive models with terrestrial experiments is essential for developing confidence in the model. As a part of this effort, AFIT has acquired a new Solar Simulation Thermal Vacuum Chamber. This research analyzed the thermal environment to which a test article is exposed within the AFIT Solar Simulation Thermal Vacuum Chamber. A computational model of the thermal environment in the chamber was created and then validated using an experimental buildup approach through thermal balance testing of the empty chamber and an aluminum plate. First, the modeled …

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Design Of A Programmable Star Tracker-Based Reference System For A Simulated Spacecraft, Warren C. Grunwald Mar 2014

Design Of A Programmable Star Tracker-Based Reference System For A Simulated Spacecraft, Warren C. Grunwald

Theses and Dissertations

The main objective of this research effort is to achieve an accuracy level for the SimSat star tracker system comparable to what is reported in current literature by various star tracker manufacturers and researchers. Previous work has provided a spherical star dome that needs to be fully populated with light sources. Programmable organic light emitting diode (OLED) panels were chosen to populate the dome to allow high contrast ratios without backlighting and increase the number of star combinations able to be represented. Noise equivalent angles less than five arcseconds (1 delta ) are achieved about the boresight axis and less …

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