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- All Subjects: Aerospace Engineering
- Genre: Masters Thesis
Description
From its founding, the United States has always claimed to be a nation of immigrants, yet in the past century the issue of immigration has become an even more contentious political issue surrounded by heated rhetoric filled with passion, but devoid of information. This thesis hopes to interrupt this rhetoric with a thorough analysis of immigration politics in Arizona through a legal lens, a theoretical lens and an empirical lens. While this thesis by no means looks at all facets of immigration politics, it informs in a manner that adds depth by providing information on the history behind, and legal arguments surrounding, the most contentious piece of immigration legislation in the United States at the moment. It then provides a theoretical analysis of how immigration legislation has created carceral networks and a panoptic gaze in Arizona specifically. It ends with a recommendation for further empirical research to partner with both the legal and theoretical frameworks. This thesis concludes that, fortified with over a century of case law, the plenary power doctrine is unwavering, and it makes federal immigration legislation an overly powerful tool in our political system from which the courts can offer little if any protection. Congress walks a fine line between preempting immigration regulation and devolving immigration regulation. SB 1070 and the 287(g) program are two contested areas of immigration regulation, which both exhibit and alter the power relationships of immigration politics in Arizona. Additionally, the application of the theories of Michel Foucault illuminates the power relationships at play in Arizona - from the power relationships among nation states in the broader political arena of geopolitics and colonialism to the face-to-face power relationship between a police officer and a stopped/detained/arrested person in a Foucauldian carceral network. This thesis ends with a call for empirical research that would yield an opportunity to analyze these relationships. This thesis discusses the importance of empirical study. It situates the study within the genre of surveillance studies and its theorists. It analyzes similar studies, and identifies the variables the most illuminating for this analysis. This thesis is written in the hope that a researcher will pick up where this thesis has left off.
ContributorsBycura, Marquette (Author) / Schweitzer, Nick (Thesis advisor) / Vargas, Perla (Committee member) / Simmons, William (Committee member) / Arizona State University (Publisher)
Created2011
Description
Fixed-pointer moving-scale tape displays are a compact way to present wide range dynamic data, and are commonly employed in aircraft and spacecraft to display the primary parameters of airspeed, altitude and heading. A limitation of the moving tape format is its inability to natively display off scale target, reference or 'bug' values. The hypothesis tested was that a non-linear fisheye presentation (made possible by modern display technology) would maintain the essential functionality and compactness of existing moving tape displays while increasing situational awareness by ecologically displaying a wider set of reference values. Experimentation showed that the speed and accuracy of reading the center system value was not significantly changed with two types of expanded range displays. The limited situational awareness tests did not show a significant improvement with the new displays, but since no functionality was degraded further testing of expanded range displays may be productive.
ContributorsEnglish, Dave (Author) / Branaghan, Russell J (Thesis advisor) / Cooke, Nancy J. (Committee member) / Sanchez, Christopher A (Committee member) / Arizona State University (Publisher)
Created2012
Description
Composite materials are increasingly being used in aircraft, automobiles, and other applications due to their high strength to weight and stiffness to weight ratios. However, the presence of damage, such as delamination or matrix cracks, can significantly compromise the performance of these materials and result in premature failure. Structural components are often manually inspected to detect the presence of damage. This technique, known as schedule based maintenance, however, is expensive, time-consuming, and often limited to easily accessible structural elements. Therefore, there is an increased demand for robust and efficient Structural Health Monitoring (SHM) techniques that can be used for Condition Based Monitoring, which is the method in which structural components are inspected based upon damage metrics as opposed to flight hours. SHM relies on in situ frameworks for detecting early signs of damage in exposed and unexposed structural elements, offering not only reduced number of schedule based inspections, but also providing better useful life estimates. SHM frameworks require the development of different sensing technologies, algorithms, and procedures to detect, localize, quantify, characterize, as well as assess overall damage in aerospace structures so that strong estimations in the remaining useful life can be determined. The use of piezoelectric transducers along with guided Lamb waves is a method that has received considerable attention due to the weight, cost, and function of the systems based on these elements. The research in this thesis investigates the ability of Lamb waves to detect damage in feature dense anisotropic composite panels. Most current research negates the effects of experimental variability by performing tests on structurally simple isotropic plates that are used as a baseline and damaged specimen. However, in actual applications, variability cannot be negated, and therefore there is a need to research the effects of complex sample geometries, environmental operating conditions, and the effects of variability in material properties. This research is based on experiments conducted on a single blade-stiffened anisotropic composite panel that localizes delamination damage caused by impact. The overall goal was to utilize a correlative approach that used only the damage feature produced by the delamination as the damage index. This approach was adopted because it offered a simplistic way to determine the existence and location of damage without having to conduct a more complex wave propagation analysis or having to take into account the geometric complexities of the test specimen. Results showed that even in a complex structure, if the damage feature can be extracted and measured, then an appropriate damage index can be associated to it and the location of the damage can be inferred using a dense sensor array. The second experiment presented in this research studies the effects of temperature on damage detection when using one test specimen for a benchmark data set and another for damage data collection. This expands the previous experiment into exploring not only the effects of variable temperature, but also the effects of high experimental variability. Results from this work show that the damage feature in the data is not only extractable at higher temperatures, but that the data from one panel at one temperature can be directly compared to another panel at another temperature for baseline comparison due to linearity of the collected data.
ContributorsVizzini, Anthony James, II (Author) / Chattopadhyay, Aditi (Thesis advisor) / Fard, Masoud (Committee member) / Papandreou-Suppappola, Antonia (Committee member) / Arizona State University (Publisher)
Created2012
Description
The Magnetoplasmadynamic (MPD) thruster is an electromagnetic thruster that produces a higher specific impulse than conventional chemical rockets and greater thrust densities than electrostatic thrusters, but the well-known operational limit---referred to as ``onset"---imposes a severe limitation efficiency and lifetime. This phenomenon is associated with large fluctuations in operating voltage, high rates of electrode erosion, and three-dimensional instabilities in the plasma flow-field which cannot be adequately represented by two-dimensional, axisymmetric models. Simulations of the Princeton Benchmark Thruster (PBT) were conducted using the three-dimensional version of the magnetohydrodynamic (MHD) code, MACH. Validation of the numerical model is partially achieved by comparison to equivalent simulations conducted using the well-established two-dimensional, axisymmetric version of MACH. Comparisons with available experimental data was subsequently performed to further validate the model and gain insights into the physical processes of MPD acceleration. Thrust, plasma voltage, and plasma flow-field predictions were calculated for the PBT operating with applied currents in the range $6.5kA < J < 23.25kA$ and mass-flow rates of $1g/s$, $3g/s$, and $6g/s$. Comparisons of performance characteristics between the two versions of the code show excellent agreement, indicating that MACH3 can be expected to be as predictive as MACH2 has demonstrated over multiple applications to MPD thrusters. Predicted thrust for operating conditions within the range which exhibited no symptoms of the onset phenomenon experimentally also showed agreement between MACH3 and experiment well within the experimental uncertainty. At operating conditions beyond such values , however, there is a discrepancy---up to $\sim20\%$---which implies that certain significant physical processes associated with onset are not currently being modeled. Such processes are also evident in the experimental total voltage data, as is evident by the characteristic ``voltage hash", but not present in predicted plasma voltage. Additionally, analysis of the predicted plasma flow-field shows no breakdown in azimuthal symmetry, which is expected to be associated with onset. This implies that perhaps certain physical processes are modeled by neither MACH2 nor MACH3; the latter indicating that such phenomenon may not be inherently three dimensional and related to the plasma---as suggested by other efforts---but rather a consequence of electrode material processes which have not been incorporated into the current models.
ContributorsParma, Brian (Author) / Mikellides, Pavlos G (Thesis advisor) / Squires, Kyle (Committee member) / Herrmann, Marcus (Committee member) / Arizona State University (Publisher)
Created2011
Description
This thesis uses an aircraft aerodynamic model and propulsion data, which
represents a configuration similar to the Airbus A320, to perform trade studies to understand the weight and configuration effects of “out-of-trim” flight during takeoff, cruise, initial approach, and balked landing. It is found that flying an aircraft slightly above the angle of attack or pitch angle required for a trimmed, stabilized flight will cause the aircraft to lose speed rapidly. This effect is most noticeable for lighter aircraft and when one engine is rendered inoperative. In the event of an engine failure, if the pilot does not pitch the nose of the aircraft down quickly, speed losses are significant and potentially lead to stalling the aircraft. Even when the risk of stalling the aircraft is small, the implications on aircraft climb performance, obstacle clearance, and acceleration distances can still become problematic if the aircraft is not flown properly. When the aircraft is slightly above the trimmed angle of attack, the response is shown to closely follow the classical phugoid response where the aircraft will trade speed and altitude in an oscillatory manner. However, when the pitch angle is slightly above the trimmed condition, the aircraft does not show this phugoid pattern but instead just loses speed until it reaches a new stabilized trajectory, never having speed and altitude oscillate. In this event, the way a pilot should respond to both events is different and may cause confusion in the cockpit.
represents a configuration similar to the Airbus A320, to perform trade studies to understand the weight and configuration effects of “out-of-trim” flight during takeoff, cruise, initial approach, and balked landing. It is found that flying an aircraft slightly above the angle of attack or pitch angle required for a trimmed, stabilized flight will cause the aircraft to lose speed rapidly. This effect is most noticeable for lighter aircraft and when one engine is rendered inoperative. In the event of an engine failure, if the pilot does not pitch the nose of the aircraft down quickly, speed losses are significant and potentially lead to stalling the aircraft. Even when the risk of stalling the aircraft is small, the implications on aircraft climb performance, obstacle clearance, and acceleration distances can still become problematic if the aircraft is not flown properly. When the aircraft is slightly above the trimmed angle of attack, the response is shown to closely follow the classical phugoid response where the aircraft will trade speed and altitude in an oscillatory manner. However, when the pitch angle is slightly above the trimmed condition, the aircraft does not show this phugoid pattern but instead just loses speed until it reaches a new stabilized trajectory, never having speed and altitude oscillate. In this event, the way a pilot should respond to both events is different and may cause confusion in the cockpit.
ContributorsDelisle, Mathew Robert (Author) / Takahashi, Timothy (Thesis advisor) / White, Daniel (Committee member) / Niemczyk, Mary (Committee member) / Arizona State University (Publisher)
Created2018
Description
There is a growing need for interplanetary travel technology development. There are hence plans to build deep space human habitats, communication relays, and fuel depots. These can be classified as large space structures. To build large structures, it is essential that these are modular in nature. With modularization of structures, it becomes essential that interconnection of modules is developed. Docking systems enable interconnection of modules. The state-of-the-art technology in docking systems is the Power Data Grapple Fixture (PDGF), used on the International Space Station by the Canadarm2 robotic arm to grapple, latch onto and provide power to the object it has grappled. The PDGF is operated by highly skilled astronauts on the ISS and are prone to human errors. Therefore, there is a need for autonomous docking. Another issue with the PDGF is that it costs around 1 to 2 million US dollars to build the 26-inch diameter docking mechanism. Hence, there is a growing need to build a lower cost and scalable, smaller docking systems. Building scalable smaller docking systems will hence enable testing them on small satellites. With the increasing need for small, low cost, autonomous docking systems, this thesis has been proposed. This thesis focuses on modeling and autonomous control of an electromagnetic probe and cone docking mechanism. The electromagnetic docking system is known to be a highly nonlinear system. Hence, this work discusses various control strategies for this docking system using a levitation strategy.
ContributorsRavindran, Aaditya (Author) / Thangavelutham, Jekanthan (Thesis advisor) / Barnaby, Hugh James (Thesis advisor) / Shafique, Ashfaque Bin (Committee member) / Arizona State University (Publisher)
Created2018
Description
VTOL drones were designed and built at the beginning of the 20th century for military applications due to easy take-off and landing operations. Many companies like Lockheed, Convair, NASA and Bell Labs built their own aircrafts but only a few from them came in to the market. Usually, flight automation starts from first principles modeling which helps in the controller design and dynamic analysis of the system.
In this project, a VTOL drone with a shape similar to a Convair XFY-1 is studied and the primary focus is stabilizing and controlling the flight path of the drone in
its hover and horizontal flying modes. The model of the plane is obtained using first principles modeling and controllers are designed to stabilize the yaw, pitch and roll rotational motions.
The plane is modeled for its yaw, pitch and roll rotational motions. Subsequently, the rotational dynamics of the system are linearized about the hover flying mode, hover to horizontal flying mode, horizontal flying mode, horizontal to hover flying mode for ease of implementation of linear control design techniques. The controllers are designed based on an H∞ loop shaping procedure and the results are verified on the actual nonlinear model for the stability of the closed loop system about hover flying, hover to horizontal transition flying, horizontal flying, horizontal to hover transition flying. An experiment is conducted to study the dynamics of the motor by recording the PWM input to the electronic speed controller as input and the rotational speed of the motor as output. A theoretical study is also done to study the thrust generated by the propellers for lift, slipstream velocity analysis, torques acting on the system for various thrust profiles.
In this project, a VTOL drone with a shape similar to a Convair XFY-1 is studied and the primary focus is stabilizing and controlling the flight path of the drone in
its hover and horizontal flying modes. The model of the plane is obtained using first principles modeling and controllers are designed to stabilize the yaw, pitch and roll rotational motions.
The plane is modeled for its yaw, pitch and roll rotational motions. Subsequently, the rotational dynamics of the system are linearized about the hover flying mode, hover to horizontal flying mode, horizontal flying mode, horizontal to hover flying mode for ease of implementation of linear control design techniques. The controllers are designed based on an H∞ loop shaping procedure and the results are verified on the actual nonlinear model for the stability of the closed loop system about hover flying, hover to horizontal transition flying, horizontal flying, horizontal to hover transition flying. An experiment is conducted to study the dynamics of the motor by recording the PWM input to the electronic speed controller as input and the rotational speed of the motor as output. A theoretical study is also done to study the thrust generated by the propellers for lift, slipstream velocity analysis, torques acting on the system for various thrust profiles.
ContributorsRAGHURAMAN, VIGNESH (Author) / Tsakalis, Konstantinos (Thesis advisor) / Rodriguez, Armando (Committee member) / Yong, Sze Zheng (Committee member) / Arizona State University (Publisher)
Created2018
Description
The aviation industry is considered to be the safest when it comes to transportation of people and property. The standards by which companies provide air transportation are held are very high. Nevertheless, a shortage in the number of pilots exists and companies must look for ways to meet demands. One of the ways to resolve this issue is to introduce unmanned systems on a broader scale – to transport people and property. The public’s perception regarding this issue has not been well documented. This survey identified what the public’s attitude is towards the use of these systems. One hundred fifty-seven people participated in this survey. Statistical analyses were conducted to determine if participant demographics, previous aviation background, and comfort levels were significantly related to various transportation technologies. Those who were comfortable or uncomfortable with self-driving cars kept their same comfort level for other technologies such as drone delivery services. The survey also revealed that the vast majority of respondents did not feel comfortable being a passenger on fully autonomous aircraft. With an overwhelming percentage of society not comfortable with the idea of there being no pilot for the aircraft, it is important for companies working to implement this technology to pay close attention to the public perception of autonomous aircraft.
ContributorsWollert, Matthew Benjamin (Author) / Niemczyk, Mary (Thesis advisor) / Nullmeyer, Robert (Committee member) / Wallmueller, Katherine (Committee member) / Arizona State University (Publisher)
Created2018
Description
The advancements in additive manufacturing have made it possible to bring life to designs
that would otherwise exist only on paper. An excellent example of such designs
are the Triply Periodic Minimal Surface (TPMS) structures like Schwarz D, Schwarz
P, Gyroid, etc. These structures are self-sustaining, i.e. they require minimal supports
or no supports at all when 3D printed. These structures exist in stable form in
nature, like butterfly wings are made of Gyroids. Automotive and aerospace industry
have a growing demand for strong and light structures, which can be solved using
TPMS models. In this research we will try and understand some of the properties of
these Triply Periodic Minimal Surface (TPMS) structures and see how they perform
in comparison to the conventional models. The research was concentrated on the
mechanical, thermal and fluid flow properties of the Schwarz D, Gyroid and Spherical
Gyroid Triply Periodic Minimal Surface (TPMS) models in particular, other Triply
Periodic Minimal Surface (TPMS) models were not considered. A detailed finite
element analysis was performed on the mechanical and thermal properties using ANSYS
19.2 and the flow properties were analyzed using ANSYS Fluent under different
conditions.
that would otherwise exist only on paper. An excellent example of such designs
are the Triply Periodic Minimal Surface (TPMS) structures like Schwarz D, Schwarz
P, Gyroid, etc. These structures are self-sustaining, i.e. they require minimal supports
or no supports at all when 3D printed. These structures exist in stable form in
nature, like butterfly wings are made of Gyroids. Automotive and aerospace industry
have a growing demand for strong and light structures, which can be solved using
TPMS models. In this research we will try and understand some of the properties of
these Triply Periodic Minimal Surface (TPMS) structures and see how they perform
in comparison to the conventional models. The research was concentrated on the
mechanical, thermal and fluid flow properties of the Schwarz D, Gyroid and Spherical
Gyroid Triply Periodic Minimal Surface (TPMS) models in particular, other Triply
Periodic Minimal Surface (TPMS) models were not considered. A detailed finite
element analysis was performed on the mechanical and thermal properties using ANSYS
19.2 and the flow properties were analyzed using ANSYS Fluent under different
conditions.
ContributorsRaja, Faisal (Author) / Phelan, Patrick (Thesis advisor) / Bhate, Dhruv (Committee member) / Rykaczewski, Konrad (Committee member) / Arizona State University (Publisher)
Created2019
Description
The focus of this study is on evaluating the perceived service quality of a passenger using Self Service Technologies (SST) based service delivery systems at airports. Previously, studies have been conducted to evaluate the benefits of these service delivery systems for the service providers and in theory, the benefits the passengers or customers may receive from using these SSTs. However, not much research has been done comparing the benefits passengers perceive from the SSTs and how the same compares with the benefits perceived by passengers while using a conventional service-employee based service delivery system, for example, manned check-in desks at airports. The data for the study was collected by surveying passengers using the scale questionnaire designed by Lin and Hsieh in 2011, named SSTQUAL (Self Service Technologies Quality), to evaluate service quality delivered by SST based service delivery systems in terms of perceived functionality, enjoyment, design-assurance-convenience, security/privacy and customization. These different dimensions were compared among passengers who utilized Self Service Kiosks (SSKs) and passengers who used check-in-desks to check their luggage in. The data derived from the responses was analyzed using Multivariate Analysis of Variance (MANOVA) to compare the between-subject effects of the dimensions as well as the overall multivariate significance in the difference between the service quality perceived between the two check-in methods. It was found that though the cumulative perceived service quality was not influenced by the method of check-in, individual service quality dimensions like Enjoyment, Design, Convenience and Assurance were influenced by the check-in method. Positive correlation was also established between the method of check-in and customer behavioral intentions of recommending and using the respective airline’s service again as well as going through the process of using the respective airline’s SST again.
Keywords: Self-Service Technologies, SSTQUAL, service-quality parameters, self check-in kiosks, manned check-in desks, technological readiness, customer behavioral intentions, MANOVA.
Keywords: Self-Service Technologies, SSTQUAL, service-quality parameters, self check-in kiosks, manned check-in desks, technological readiness, customer behavioral intentions, MANOVA.
ContributorsSingh, Aditya (Author) / Niemczyk, Mary C (Thesis advisor) / Gray, Robert (Committee member) / Hartman, James (Committee member) / Arizona State University (Publisher)
Created2018