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Air Force Institute of Technology

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Planning Coverage Of Points Of Interest Via Multiple Imaging Surveillance Assets: A Multi-Model Approach, Sarah E. Jackson Mar 2003

Planning Coverage Of Points Of Interest Via Multiple Imaging Surveillance Assets: A Multi-Model Approach, Sarah E. Jackson

Theses and Dissertations

For the United States to maintain information superiority, it is necessary to have a means of allocating intelligence-gathering assets to collect information on particular points of interest. In today's geopolitical environment, however, the number of points of interest is growing rapidly, whereas the number of available assets is not. To aid in maintaining information superiority, this research explores the use of a Multi-Modal Goal Programming Resource Constrained Project Scheduling approach for allocating imaging surveillance assets (land, air, sea, and space) to a set of points of interest for a given time period. The multiple objectives of this formulation are to …

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A Stochastic Model For Joint Reception, Staging, Onward Movement, And Integration (Jrsoi), Nathan P. Sherman Mar 2003

A Stochastic Model For Joint Reception, Staging, Onward Movement, And Integration (Jrsoi), Nathan P. Sherman

Theses and Dissertations

A stochastic model for the performance evaluation of a key phase in the deployment process, namely Joint Reception, Staging, Onward Movement, and Integration (JRSOI) is presented. The process is modeled as an open, multi-class tandem queueing network wherein personnel and various classes of cargo are modeled as the flow entities and the stages of the process constitute individual queueing stations. Single and multiple-class models at both low and high resolutions are presented. No analytical stochastic model of this process currently exists in the literature or in practice. The model provides a quick look at key aggregate performance measures such as …

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Models For Sortie Generation With Autonomic Logistics, Nicholaus A. Yager Mar 2003

Models For Sortie Generation With Autonomic Logistics, Nicholaus A. Yager

Theses and Dissertations

The primary objective of this research is to investigate the impact of an autonomic logistics system (ALS) on the sortie generation process for an individual airbase. As in some prior studies of this process, the methodology used to model the sortie generation process is a queueing network containing fork-join nodes for concurrent maintenance activities. The sortie generation rate is commonly regarded as the primary performance measure of the sortie generation process. This measure coincides with the throughput and is used to compare two models: (1) pre-ALS operations and (2) ALS-enhanced airbase operations. Analysis of the models shows that the ALS …

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Explicit Building-Block Multiobjective Genetic Algorithms: Theory, Analysis, And Developing, Jesse B. Zydallis Mar 2003

Explicit Building-Block Multiobjective Genetic Algorithms: Theory, Analysis, And Developing, Jesse B. Zydallis

Theses and Dissertations

This dissertation research emphasizes explicit Building Block (BB) based MO EAs performance and detailed symbolic representation. An explicit BB-based MOEA for solving constrained and real-world MOPs is developed the Multiobjective Messy Genetic Algorithm II (MOMGA-II) which is designed to validate symbolic BB concepts. The MOMGA-II demonstrates that explicit BB-based MOEAs provide insight into solving difficult MOPs that is generally not realized through the use of implicit BB-based MOEA approaches. This insight is necessary to increase the effectiveness of all MOEA approaches. In order to increase MOEA computational efficiency parallelization of MOEAs is addressed. Communications between processors in a parallel MOEA …

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The Effect Of A Hard Coating On The Damping And Fatigue Life Of Titanium, Frank T. Ivancic Mar 2003

The Effect Of A Hard Coating On The Damping And Fatigue Life Of Titanium, Frank T. Ivancic

Theses and Dissertations

This project compares the damping and fatigue life of bare titanium plates to those coated with magnesium aluminate spinel (mag spinel). Two different coating thicknesses were tested: .005" per side and .010" per side (total thicknesses of .010" and .020"). Dynamic ping tests were conducted on all specimens to determine their resonance frequencies. Laser vibrometry was used to determine the mode at each resonance frequency. Damping ratios were determined through the use of sine sweeps. A vibration mode was selected at which to fatigue the specimens, and the stress pattern was analyzed utilizing the Stress Pattern Analysis by Thermal Emissions …

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Sensor-Craft Analytical Certification, Ronald W. Roberts Jr. Mar 2003

Sensor-Craft Analytical Certification, Ronald W. Roberts Jr.

Theses and Dissertations

This study developed a multi-disciplinary conceptual design of a joined-wing sensor-craft. Initial analysis was conducted using an aluminum model. Linear fully stressed design and flexible aerodynamic trim were used to converge to a minimum weight design that was aerodynamically stable. This optimized design was buckling safe. A similar optimization process using non-linear fully stressed design and flexible aerodynamic trim was conducted. The non- linear structurally deformation was over ten times greater than the linear structural deformation. Again, the model was structurally and aerodynamically optimized. The linear optimization was repeated using a composite structural model incorporating Conformal Load-bearing Antenna Structures. This …

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Inquisitive Pattern Recognition, Amy L. Magnus Mar 2003

Inquisitive Pattern Recognition, Amy L. Magnus

Theses and Dissertations

The Department of Defense and the Department of the Air Force have funded automatic target recognition for several decades with varied success. The foundation of automatic target recognition is based upon pattern recognition. In this work, we present new pattern recognition concepts specifically in the area of classification and propose new techniques that will allow one to determine when a classifier is being arrogant. Clearly arrogance in classification is an undesirable attribute. A human is being arrogant when their expressed conviction in a decision overstates their actual experience in making similar decisions. Likewise given an input feature vector, we say …

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Stochastic Intra-Cellular Modeling, Thomas E. Hopkins Mar 2003

Stochastic Intra-Cellular Modeling, Thomas E. Hopkins

Theses and Dissertations

Air Force personnel may sometimes come into contact with potentially harmful chemicals while performing their duties. Of course the Air Force desires to keep any potential health risks to its members to a minimum. To this end the Air Force would like to identify which chemicals are toxic, their level of toxicity, and the processes by which these chemicals disrupt normal biological activities at the cellular level. The development of mathematical models can be of great benefit to toxicity studies. Because real world systems involve randomness, that is noise, and the desire is to create mathematical models to represent those …

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

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Estimating Engineering And Manufacturing Development Cost Risk Using Logistic And Multiple Regression, John V. Bielecki Mar 2003

Estimating Engineering And Manufacturing Development Cost Risk Using Logistic And Multiple Regression, John V. Bielecki

Theses and Dissertations

Cost Growth in Department of Defense (DoD) major weapon systems has been an on-going problem for more than 30 years. Previous research has demonstrated the use of a two-step logistic and multiple regression methodology to predicting cost growth produces desirable results versus traditional single-step regression. This research effort validates, and further explores the use of a two-step procedure for assessing DoD major weapon system cost growth using historical data, We compile programmatic data from the Selected Acquisition Reports (SARs) between 1990 and 2001 for programs covering all defense departments. Our analysis concentrates on cost growth in the research and development …

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Estimating Procurement Cost Growth Using Logistic And Multiple Regression, Gary W. Moore Mar 2003

Estimating Procurement Cost Growth Using Logistic And Multiple Regression, Gary W. Moore

Theses and Dissertations

Cost Growth in Department of Defense (DoD) major systems has been an ongoing problems for more than 30 years. Previous research has demonstrated the use of two-step logistic and multiple regression methodology to predicting cost growth produces desirable results traditional single-step regression. This research effort validates, and further explores the use of a two-step procedure for assessing DoD major weapon system cost growth using historical data. We compile programmatic data from the Selected Acquisition Reports (SARs) between 1990 and 2001 for programs covering all defense departments. Our analysis concentrates on cost growth in procurement dollar accounts for the Engineering and …

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The Development Of An Integrated Measure Of Readiness For Change Instrument And Its Application On Asc/Pk, Steven W. Clark Mar 2003

The Development Of An Integrated Measure Of Readiness For Change Instrument And Its Application On Asc/Pk, Steven W. Clark

Theses and Dissertations

Organizations are continually forced to implement changes due to a myriad of external and internal influences, Despite the fact that organizations are predominantly in a perpetual state of change, recent research has shown that nearly 75% that have initiated large-scale change efforts have not realized the significant organizational improvements that were intended, As a preemptive measure, organizational managers are being encouraged to gauge their organization's readiness prior to implementing change initiatives, Unfortunately, over 40 unique instruments currently exist that purport to measure some aspect of readiness, Because of limited perspective, no one instrument has emerged as the standard and they …

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Developing Cost Per Flying Hour Factors For The Operations And Maintenance Phase Of The Satellite Life Cycle, Anthony K. Kimbrough Mar 2003

Developing Cost Per Flying Hour Factors For The Operations And Maintenance Phase Of The Satellite Life Cycle, Anthony K. Kimbrough

Theses and Dissertations

The purpose of this thesis was to develop cost per flying hour factors for the operations and maintenance (O&M) phase of the satellite life cycle. At a time when space system platforms are becoming some of the most strategic weapons in the military arsenal, it is critical that accurate cost models and factors be developed to assist in budgeting for the O&M of these assets.

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Combat Air Forces Campaign Level Modernization Planning-A Study In Group Decision Making, Ian L. Walker Mar 2003

Combat Air Forces Campaign Level Modernization Planning-A Study In Group Decision Making, Ian L. Walker

Theses and Dissertations

Modernization is a critical component of the current transformation effort within the Department of Defense (DoD) Effective and efficient modernization planning will provide for the improved allocation of limited funding. The Air Force currently conducts capabilities based modernization planning to identify shortfalls. Air Combat Command (ACC) utilizes multi-objective decision analysis (MODA) techniques to support the modernization planning process (MPP). A MODA model has been created to identify and quantify capability shortfalls across a diverse range of mission areas. Groups of subject matter experts are utilized to provide model inputs improving the usefulness and credibility of the model. The intent of …

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An Analysis Of The Implementation Of Acquisition Reform Initiatives And Contract Cost Variance, Mark A. Holbrook Mar 2003

An Analysis Of The Implementation Of Acquisition Reform Initiatives And Contract Cost Variance, Mark A. Holbrook

Theses and Dissertations

This thesis examines the impact of acquisition reform initiatives implemented since 1993 on contract cost performance. Many initiatives implemented during the 1990s focused on saving the government money in procuring weapon systems. For decades, cost overruns have plagued Department of Defense weapons systems development and procurement costing the government money. The passage of the Federal Acquisition Streamlining Act (FASA) of 1994 and the Clinger-Cohen Act of 1996, marked significant congressional action on aiding the Department of Defense develop and procure systems cheaper. Conclusions drawn in this thesis may aid leadership in supporting current initiatives and drafting new changes.

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A Three-Dimensional Heads-Up Primary Navigation Reference Display For Paratroopers Performing High Altitude High Open Jumps, Brian A. Balazs Mar 2003

A Three-Dimensional Heads-Up Primary Navigation Reference Display For Paratroopers Performing High Altitude High Open Jumps, Brian A. Balazs

Theses and Dissertations

The Department of Defense (DoD) relies on the para-dropping of resources to meet different objectives in order to accomplish missions during peace-time, war-time, or military operations other than war. The resources dropped to the ground via parachute range from supplies and equipment to the most valued asset, people. Tactics have been developed to increase the safety of troops parachuting into areas of conflict. These tactics include high-altitude high-opening (HAHO) jumping and night jumping. HAHO jumping allows paratroopers to travel large distances in the air away from the path of the delivering aircraft. While night jumping, done with the aid of …

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Integrating Cost As An Independent Variable Analysis With Evolutionary Acquisition - A Multiattribute Design Evaluation Approach, Marc T. Lewis Mar 2003

Integrating Cost As An Independent Variable Analysis With Evolutionary Acquisition - A Multiattribute Design Evaluation Approach, Marc T. Lewis

Theses and Dissertations

Guidance from the Under Secretary of Defense for Acquisition, Technology, and Logistics (USD(AT&L)) requires 100 percent of defense programs to incorporate cost as an independent variable (CAIV) and evolutionary acquisition (EA) plans within their management baselines. Historically, these two concepts have been implemented independent of one another. In reality, CAIV and EA are tightly coupled, Integration of these two initiatives enables warfighters and developers to better allocate constrained resources, respond to fluctuations in program funding, and plan for future development activities. This research creates a decision tool to assist the DoD acquisition community in satisfying the intent of the USD(AT&L) …

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A Comparative Analysis Of The Cost Estimating Error Risk Associated With Fly Away Costs Vs Individual Components Of Aircraft, Jonathan D. Ritschel Mar 2003

A Comparative Analysis Of The Cost Estimating Error Risk Associated With Fly Away Costs Vs Individual Components Of Aircraft, Jonathan D. Ritschel

Theses and Dissertations

A shrinking workforce, unstable budgets, and rapidly changing objectives under stricter time constraints characterize today's cost analysis and acquisition environment. In concert with this environment, cost analyst positions have rapidly decreased as demonstrated by Aeronautical Systems Centers 54% decline in total authorized slots from 1992 to 2001. The question is how to deal with this more with less' mentality. The purpose of this research is to investigate and measure the risks associated with taking a macro versus micro approach to aircraft cost estimation. By analyzing the fidelity of a cost estimate developed at the flyaway cost level versus a cost …

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Searching System Call Information For Clues: The Effects Of Intrusions Of Processes, Mark G. Reith Mar 2003

Searching System Call Information For Clues: The Effects Of Intrusions Of Processes, Mark G. Reith

Theses and Dissertations

The United States Air Force extensively uses information systems as a tool managing and maintaining its information. The increased dependence on these systems in recent years has necessitated the need for protection front threats of information warfare and cyber terrorism. One type of protection utilizes intrusion detection systems to provide indications that intrusive behavior has occurred. Other types of protection may include packet filtering, cryptography and strong user authentication. Traditional approaches toward intrusion detection rely on features that are external to computer processes. By treating processes as black-boxes, intrusion detection systems may miss a wealth of information that could be …

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Performance Evaluation And Analysis Of Effective Range And Data Throughput For Unmodified Bluetooth Communication Devices, Timothy F. Kneeland Mar 2003

Performance Evaluation And Analysis Of Effective Range And Data Throughput For Unmodified Bluetooth Communication Devices, Timothy F. Kneeland

Theses and Dissertations

The DoD and the Air Force continually seek to incorporate new technology in an effort to improve communication, work effectiveness, and efficiency. Office devices utilizing Bluetooth technology simplify device configuration and communication. They provide a means to communicate wirelessly over short distances thereby eliminating the need for different vendor specific cables and interfaces. One of the key concerns involved in incorporating new communication technology is security; the fundamental security concern of wireless communication is interception. Studies focusing on IEEE 802.11b have shown vulnerability zones around many DoD installations that reflect the ranges at which wireless communications using the 802.11b standard …

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Adjusting Sensing Range To Maximize Throughput On Ad-Hoc Multi-Hop Wireless Networks, Christopher K. Roberts Mar 2003

Adjusting Sensing Range To Maximize Throughput On Ad-Hoc Multi-Hop Wireless Networks, Christopher K. Roberts

Theses and Dissertations

The use of ad-hoc wireless networks is becoming common within the United States Air Force. Such networks are able to be implemented where traditional wired networks are either impractical or too expensive. As the miniaturization of communication devices continues, it is becoming increasingly common for mobile devices to communicate directly with each other, eliminating the need for center access points. Such a network is referred to as a multi-hop ad-hoc network, or simply a multi-hop network. Most multi-hop network protocols use some form of carrier sensing to determine if the wireless channel is in use. A large sensing range can …

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Decision Analysis Model For Refreshment Of Geobase Imagery: Basis For Investment Strategy, Matthew S. Craig Mar 2003

Decision Analysis Model For Refreshment Of Geobase Imagery: Basis For Investment Strategy, Matthew S. Craig

Theses and Dissertations

The United States Air Force is in the process of implementing GeoBase, an initiative to change how geospatial information resources are being acquired, implemented, exploited, and sustained on USAF installations around the world. Using GeoBase increases situational awareness and minimizes decision risk for all installation personnel GeoBase is a geographic information system, using commercial-off-the-shelf software to provide one source for spatial information on an installation. GeoBase uses imagery as one layer of information. The accuracy of the imagery directly impacts the effectiveness of GeoBase. The purpose of this thesis was to develop a decision model to be used in determining …

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Optimizing An In Situ Bioremediation Technology To Manage Perchlorate-Contaminated Groundwater, Mark R. Knarr Mar 2003

Optimizing An In Situ Bioremediation Technology To Manage Perchlorate-Contaminated Groundwater, Mark R. Knarr

Theses and Dissertations

Combining horizontal flow treatment wells (HFTWs) with in situ biodegradation is an innovative approach with the potential to remediate perchlorate-contaminated groundwater. A technology model was recently developed that combines the groundwater flow induced by HFTWs with in situ biodegration processes that result from using the HFTWs to mix electron donor into perchlorate-contaminated groundwater. A field demonstration of this approach is planned to begin this year. In order to apply the technology in the field, project managers need to understand how contaminated site conditions and technology design parameters impact technology performance. One way to gain this understanding is to use the …

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A System Dynamics Investigation Of Genetic Drift And Translocation In The Red-Cockaded Woodpecker Metapopulation, Jason E. Yates Mar 2003

A System Dynamics Investigation Of Genetic Drift And Translocation In The Red-Cockaded Woodpecker Metapopulation, Jason E. Yates

Theses and Dissertations

The red-cockaded woodpecker (Picoides borealis) is classified under the Endangered Species Act of 1973 as an endangered species As such, the red-cockaded woodpecker (RCW) is afforded strict protection in an effort to return the RCW population to a self-sustainable level. Endemic to southeastern United States mature pine forests, the presence of the RCW impacts the operations of many Department of Defense (DoD) installations. A particular challenge in sustaining what are often small populations of RCW at these locations is the loss of genetic variation due to genetic drift. The optimal method for mitigating such loss is through the artificial immigration, …

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Analysis Of Anion Distributions In The Developing Strata Of A Constructed Wetland Used For Chlorinated Ethene Remediation, Joshua D. Kovacic Mar 2003

Analysis Of Anion Distributions In The Developing Strata Of A Constructed Wetland Used For Chlorinated Ethene Remediation, Joshua D. Kovacic

Theses and Dissertations

Perchloroethene (PCE), Trichloroethene (TCE) and their degradation products are among the most common organic groundwater contaminants in the United States. Constructed wetlands utilizing upward flow harbor reduction-oxidation conditions that have demonstrated the potential to promote both partial and total mineralization of PCE and TCE through the process of natural attenuation. Organic acid and inorganic anion concentrations are indicative of reduction-oxidation processes that drive chlorinated ethene degradation. These analytes were investigated to assess their development within three vertically stratified regions of a constructed wetland cell at Wright-Patterson Air Force Base fed by groundwater contaminated with PCE and TCE. Data collected during …

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Mechanical Computing In Microelectromechanical Systems (Mems), Kenneth C. Bradley Mar 2003

Mechanical Computing In Microelectromechanical Systems (Mems), Kenneth C. Bradley

Theses and Dissertations

Mechanical computing devices in polysilicon-based microelectromechanical systems (MEMS) were designed with the goal of developing computing devices for harsh environments, such as those with high dose radiation and high temperatures, as well as devices that may be able to interface with molecular or biological computer systems. The devices that were designed include both analog and digital computing devices. The analog devices include integrators, differentials (summers), multipliers, and those that perform trigonometric functions. The digital devices that were designed are inverters, NAND, NOR, and XOR logic gates. Analog-to-digital (A-to-D) and digital-to-analog (D-to-A) converters were also designed. The designs were submitted to …

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Feature Guided Image Registration Applied To Phase And Wavelet-Base Optic Flow, Kate R. Duffy Mar 2003

Feature Guided Image Registration Applied To Phase And Wavelet-Base Optic Flow, Kate R. Duffy

Theses and Dissertations

Optic Flow algorithms are useful in problems such as computers vision, navigational systems, and robotics. However, current algorithms are computationally expensive or lack the accuracy to be effective compared with traditionally navigation systems. Recently, lower accuracy inertial navigation systems (INS) based on Microelectromechanical systems (MEMS) technology have been proposed to replace more accurate traditional navigation systems.

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Redundant Discrete Wavelet Transform Based Super-Resolution Using Sub-Pixel Image Registration, Daniel L. Ward Mar 2003

Redundant Discrete Wavelet Transform Based Super-Resolution Using Sub-Pixel Image Registration, Daniel L. Ward

Theses and Dissertations

The limited resolution of video imagery taken by aircraft, over geographical areas of interest, hinders the accurate extraction of useful information. The frame resolution of the video is determined by the camera that created it. Information exists about the camera which can be used to increase frame resolution beyond the resolution capability of the camera. This is achieved by a process called super-resolution, which uses multiple low-resolution video frames to create one high-resolution image.

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A Comparison Of Nonlinear Algorithms To Prevent Pilot-Induced Oscillations Caused By Actuator Rate Limiting, James G. Hanley Mar 2003

A Comparison Of Nonlinear Algorithms To Prevent Pilot-Induced Oscillations Caused By Actuator Rate Limiting, James G. Hanley

Theses and Dissertations

The objective of this study was to compare the ability of the Feedback-with-Bypass (FWB) and the Derivative-Switching (DS) flight control system filters to prevent PIO during actuator rate limiting, and the filters' effects on aircraft handling qualities. This comparison was conducted in three steps: computer simulation, ground simulation in the Large Amplitude Multimode Aerospace Research Simulator (LAMARS), and flight tests conducted in the Variable Stability In-flight Simulator Test Aircraft (VISTA). During computer simulation, the FWB filter better reduced the phase lag and prevented sustained or divergent oscillations during the closed-loop analysis. During both ground simulation and flight tests, the FWB …

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Hybrid Control Strategies For Rapid, Large Angle Satellite Slew Maneuvers, David B. French Mar 2003

Hybrid Control Strategies For Rapid, Large Angle Satellite Slew Maneuvers, David B. French

Theses and Dissertations

This research investigated hybrid control strategies for rapid satellite pointing. First, a detailed computer simulation model of AFIT's SIMSAT satellite simulator was constructed. Control strategies were developed to enable the system to perform large-angle, 3-axis slewing maneuvers using a combination of both thrusters and reaction wheels. To handle the non-linear model, a State Dependent Riccati Equation controller was programmed and successfully controlled the computer-modeled satellite for any given slewing maneuver. A simpler PD controller was then programmed and demonstrated on the computer simulation of SIMSAT, using a combination of thruster and reaction wheel control inputs for large-angle single axis maneuvers …

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