Master of Science (M.S.), University of Dayton, 2023, Aerospace Engineering

There has been a recent surge in the need for unmanned aerial vehicles (UAVs), drones, and air taxis for a variety of commercial, entertainment, and military applications. New aircraft designs put forth by companies have shown to feature multiple lift producing surfaces and rotors acting in proximity to each other. These configuration choices are primarily informed by the “compactness” requirement in the design. For this reason, configurational choices are being considered that would otherwise not receive attention. Multi-wing configurations or distributed lift systems become a compelling choice in conceptual design of future UAVs and private air vehicles (PAVs) that complements the vertical takeoff and landing capabilities of the design. For multi-wing configurations to be considered in the early conceptual design process, the reliability of traditional lower order aerodynamic methods in predicting these aerodynamic effects must be determined. However, the nature of a highly distributed lift configuration, with 10 or more lifting surfaces in close proximity, does not lend itself to rapid or accurate viscous numerical solution. Moreover, highly distributed lift configurations drive individual lifting surface Reynolds numbers into a range where viscous interactions could have a profound effect on aerodynamic performance. As such, the degree of dependence of wing-wing interactions due to viscous effects could be determined in a first iteration through a reductionist approach. Focusing specifically on the three-dimensional viscous interactions and the aerodynamic forces on the upstream and downstream wings allows for a direct determination of the importance and isolated contribution of these effects. Proximity effects due to wing-wing interactions were experimentally quantified as a function of gap and stagger across a wide range of different relative angles of attack (decalage). The proximity effects and the zone of influence at different gap and stagger locations wer (open full item for complete abstract)

Committee: Sidaard Gunasekaran (Committee Chair); Aaron Altman (Committee Member); Michael Mongin (Committee Member); Markus Rumpfkeil (Committee Member) Subjects: Aerospace Engineering; Engineering; Mechanical Engineering

Master of Science, The Ohio State University, 2023, Mechanical Engineering

The purpose of this work was to design a system to enable full articulating control of the wingtips on a novel delta wing aircraft. This project is motivated by ongoing unmanned aerial vehicle research and development at The Ohio State University Research Center. A model was developed that met the four design requirements of being high-speed, highly maneuverable, aerodynamically interesting, and multi-configurable. Previous work looked at the low-speed aerodynamic characteristics of the delta wing layout with rotating wing tips that could articulate 180-degrees. The wingtips are located at 2/3rds of the half-span and are parallel to the fuselage centerline. It was found that rotating the wingtips influenced the longitudinal characteristics resulting in the ability to adjust in-flight the maneuverability characteristics of the aircraft. A design study was completed considering six different mechanism types for the articulation actuation of the wingtips. It was desired that the mechanism would have little effect on the current aircraft by minimizing mass and having no protrusion through the wing surface. A design utilizing universal joints for the transfer of torque produced by a servo motor was chosen. A prototype to serve as proof of concept was constructed at a one-third scale. Tests were performed using the prototype that proved this mechanism could fully articulate the wingtip to the needed positions, as well as perform under loads that could be seen in flight. Simulink was used in an analysis of the longitudinal dynamics. Aerodynamic stability characteristics were taken from previous wind tunnel testing. Through simulation it was shown that in the wingtips baseline position of being parallel with the rest of the wings, the aircraft has stable longitudinal characteristics. However, when the wingtips are rotated 90-degrees upwards, the delta wing aircraft has decreased stability leading to increased maneuverability.

Committee: Clifford Whitfield (Advisor); Sandra Metzler (Advisor) Subjects: Aerospace Engineering; Engineering; Mechanical Engineering

Doctor of Philosophy, Case Western Reserve University, 2020, EMC - Aerospace Engineering

For more than two decades researchers have sought to develop a micro aerial vehicle (MAV) capable of discrete remote surveillance and reconnaissance in hazardous environments where no other alternative means of observation exist. While some success has been found in multi-rotor designs such as quadcopters, these vehicles are limited in their flight duration, flight range, robustness, stealth, safety, and agility. Biology offers a source of inspiration in insect flight. Flapping-wing micro aerial vehicles (FWMAVs) have the potential to address the current shortcomings of MAVs. This dissertation approaches the development of FWMAVs by attempting to mimic two major flight components of a particular insect, the hawk moth Manduca sexta (L.). Novel methods are established to design, fabricate and assess the performance of artificial M. sexta forewings and a flapping-wing mechanism inspired by the M. sexta thorax. Results from forewing experiments indicate successful emulation of mass and forewing geometry, including camber. Flexural stiffness values are an order of magnitude greater than desired and suggest that membrane and venation structure material must change. However, lift production analysis reveals that the artificial forewings are capable of generating comparable amounts of force to naturally occurring M. sexta forewings. Kinematic simulations demonstrate advantages to using a Scotch yoke mechanism as opposed to a more traditional crank-slider mechanism to convert continuous rotary motion into oscillatory flapping-wing motion. A multibody dynamic simulation of a Scotch yoke mechanism and passively rotating forewings is developed as a tool to investigate areas of improvement for increased mechanism efficiency such as the addition of energy storing and releasing components and potential changes in mechanism geometry. Empirical performance data on various configurations of a flapping-wing system comprised of a Scotch yoke mechanism and artificial M. sexta forewings (open full item for complete abstract)

Committee: Roger Quinn Dr. (Committee Chair); Mark Willis Dr. (Committee Member); Richard Bachmann Dr. (Committee Member); Yasuhiro Kamotani Dr. (Committee Member) Subjects: Aerospace Engineering; Aerospace Materials; Engineering; Mechanical Engineering; Robotics; Robots

Master of Science (M.S.), University of Dayton, 2024, Aerospace Engineering

Recent advancements in battery technology have led to an increase in the development of electric Vertical Takeoff and Landing (eVTOL) vehicles, typically using electrically-powered propellers to generate both lift and thrust. These vehicles typically operate in low-altitude, and limited-space conditions in urban environments. Unsteady flows from building wakes or atmospheric boundary layer effects raise concern to the stability of eVTOL-capable aircraft under normal operating conditions and during transition from vertical to forward flight and vice-versa in population dense areas. Although all types of unsteady flows have been studied for decades, little has been published on the influence of unsteady flow on a propeller-wing system. Understanding of this system is crucial to ensuring the safety of not only the passengers of these VTOL aircraft, but also the safety of the public. Investigation into powered wing response to streamwise gust encounters was conducted through various propeller locations, angles of attack, reduced frequencies, and thrust levels. All experiments were run at the University of Dayton Low Speed Wind Tunnel (UD-LSWT) in its open-jet configuration. The shuttering system downstream of the test section consists of a set of rotating louvers that change angle to effectively change the blockage ratio of the wind tunnel. Different louver angles and actuation frequencies provide different velocities and reduced frequencies. Particle Image Velocimetry (PIV) was conducted on the freestream flow during actuation of the louvers to spatially characterize the angle of attack variation throughout the test section. The results from PIV were used to determine the optimal testing location and wing size for the test article. The wing was designed to be modular, accepting a number of different propeller Distribution Statement A: Approved for Public Release; Distribution is Unlimited. PA# AFRL-2024-2083 4 locations. Four total configurations were considered – (open full item for complete abstract)

Committee: Sidaard Gunasekaran (Committee Chair); Michael Mongin (Committee Member); Albert Medina (Committee Member); Markus Rumpfkeil (Committee Member) Subjects: Aerospace Engineering

Master of Science, The Ohio State University, 2020, Aero/Astro Engineering

The purpose of this work was to investigate the low-speed aerodynamic characteristics of a novel delta wing layout with deflected wing tips. This project is motivated by the ongoing unmanned aerial vehicle research and development at The Ohio State University Aerospace Research Center. The model under test for this study had four main design requirements: (1) high-speed, (2) highly maneuverable, (3) aerodynamically interesting, and (4) multi-configurable. The last three requirements are addressed directly in this report with specific emphasis on requirements two and three. A modular fuselage design satisfied requirement four, and the novel delta wing addressed requirements two and three. The novel delta wing has a leading-edge sweep of 60 degrees, a high-speed airfoil with a rounded leading-edge, and wing tips that can rotate a full 180 degrees about a hinge, located at 2/3rds of the half-span parallel to fuselage centerline. Three different wing tip deflection configurations were analyzed: positive, negative, and asymmetric. Positive wing tip deflection corresponds to the wing tips being deflected up towards the vertical tail. Negative wing tip deflection is when the wing tips are deflected down, away from the vertical tail. While the asymmetric configuration has one wing tip deflected up and the other down. Analysis on the model was completed using a panel method code and experimental wind tunnel testing. The panel method code used was OpenVSP. Upon implementing a vortex lift factor, it was determined that the delta wing results from OpenVSP were only useful for lift related data after comparing the panel method results to theory and publicly available delta wing data. The wind tunnel used for this work is located at the Aerospace Research Center. The wind tunnel is an open circuit subsonic wind tunnel with a 3'x5' test section. Aerodynamic forces were measured using an internal six-component force balance. Tests were performed at two different Reynolds numb (open full item for complete abstract)

Committee: Clifford Whitfield Dr. (Advisor); Rick Freuler Dr. (Committee Member); Matthew McCrink Dr. (Committee Member) Subjects: Aerospace Engineering

Doctor of Philosophy (PhD), Ohio University, 2019, Mass Communication (Communication)

Democracy allows a plural media landscape where different types of media perform vital functions. Over the years, the public trust towards mainstream media has been eroding, limiting their ability to fulfill democratic functions within American society. Meanwhile, the Internet has led to the proliferation of alternative media outlets on digital space. These platforms allow new outreach and mobilizing opportunities to the once peripheral alternative media. So far, the literature about alternative media have been heavily focused on left-wing alternative media outlets, while the research on alternative right-wing media has remained scarce and fragmented. Only a few studies have applied a comparative analysis approach to study these outlets. Moreover, research that examines different aspects of alternative media such as content and audience reception is rarer. This study aims to demonstrate the heterogeneity of alternative media by highlighting their history and functions within American democracy. The second goal of the study is to assess the potential of such platforms to foster political participation. This research project aims to answer the following questions: What are the roles of alternative media in American democracy? What are the ways in which right-wing and left-wing alternative media foster political participation? How do they differ or resemble? To answer these questions, I adopted a two-pronged qualitative methodology. One focuses on audience reception. The other involves a critical analysis of their content. I conducted six focus groups with 24 students. The goal of this part of the study was to understand audience perceptions and experience with alternative media. I was also interested how the alternative content informs their decisions regarding political participation. In addition to the semi-structured questions, the participants read sample articles and listened to podcast segments from the right-wing media outlet, the Daily Wire and The Ben (open full item for complete abstract)

Committee: Wolfgang Suetzl PhD (Advisor) Subjects: Mass Communications; Mass Media

Doctor of Philosophy, Miami University, 2018, Biology

The acquisition of wings was a defining moment in the evolution of insects. The novel insect wing provided insects with the ability to disperse via powered flight and with an evolutionary medium for the emergence of new traits, both of which have greatly contributed to the success of this clade. However, despite the importance of insect wings, the evolutionary origin of this structure remains a mystery. Historically, the origin of the insect wing has captivated scientists and, accordingly, it has been debated for over 200 years. Over the course of these debates, two possible wing origin tissues have been identified; a lateral outgrowth of the dorsal body wall (tergum) and ancestral proximal leg structures (pleuron in insects). However, there is still no consensus as where insect wings came from and how they have evolved. This dissertation aims to address this conundrum through the identification of wing-related structures in the wingless segments of insects (wing serial homologs) and in non-winged arthropods. The identification of structures related to wings in wingless segments can give us a better understanding of the ancestral state of the tissues that gave rise to the insect wing and provide us with a more comprehensive view of wing evolution. In the first study, we identified wing serial homologs in the wingless first thoracic segment (T1) of the beetle, Tribolium. Through our analyses, we determined that T1 of Tribolium possesses two separate wing serial homologs, one tergal and one pleural. This study provided the first functional evidence for a dual origin of insect wings, which unifies the two previous hypotheses and suggests that insect wings are formed from a merger of both tergal and pleural tissues. In the second study, to gain a better understanding of the evolutionary contribution of each of these tissues to the wing, we analyzed how each of the Tribolium T1 wing homologs contributes to a wing formed in the traditionally wingless T1 upon Hox reduction (open full item for complete abstract)

Committee: Yoshinori Tomoyasu (Advisor) Subjects: Biology; Evolution and Development

Doctor of Philosophy, The Ohio State University, 2013, Mechanical Engineering

In this thesis, first presented is an overview of inorganic-fouling and biofouling which is generally undesirable for many medical, marine, and industrial applications. A survey of nature's flora and fauna are studied in order to discover new antifouling methods that could be mimicked for engineering applications. New antifouling methods will presumably incorporate a combination of physical and chemical controls. Presented are mechanisms and experimental results focusing on laminar and turbulent drag reducing shark skin inspired riblet surfaces. This includes new laser etched and riblet film samples for closed channel drag using water, oil, and air as well as in wind tunnel. Also presented are mechanisms and experimental results focusing on the newly discovered rice and butterfly wing effect surfaces. Morphology, drag, self-cleaning, contact angle, and contact angle hysteresis data are presented to understand the role of sample geometrical dimensions, wettability, viscosity, and velocity. Hierarchical liquid repellent coatings combining nano- and micro-sized features and particles are utilized to recreate or combine various effects. Such surfaces have been fabricated with photolithography, soft lithography, hot embossing, and coating techniques. Discussion is provided along with new conceptual models describing the role of surface structures related to low drag, self-cleaning, and antifouling properties. Modeling provides design guidance when developing novel low drag and self-cleaning surfaces for medical, marine, and industrial applications.

Committee: Bharat Bhushan (Advisor) Subjects: Fluid Dynamics; Mechanical Engineering; Nanotechnology

MS, University of Cincinnati, 2005, Engineering : Mechanical Engineering

The current research focuses on studying the modal response of a joined wing aircraft based on the Sensorcraft configuration. Sensorcraft, a class of High-Altitude, Long-Endurance (HALE) aircraft, is an Unmanned Air Vehicle (UAV), and is being studied by the AFRL for applications involving telecommunication relay, environmental sensing and military reconnaissance. The Sensorcraft is designed to operate at high altitudes (60,000 ft) with low speed and for long durations of time (60 to 80 hours). At these operating conditions, the density, and hence, the Reynolds number, is low. These conditions require the Sensorcraft to operate with high lift and low drag with high-aspect ratio wings. Moreover, the vehicle must be lightweight and strong, and offer high aerodynamic performance and efficiency. The AFRL has identified a diamond shape joined wing configuration for Sensorcraft due to the primary structural advantage of strength as each wing braces the other against lift loads.The University of Cincinnati (UC), along with its partners, AFRL and Ohio State University are working together to study the complete nonlinear aeroelastic behavior of the joined-wing model. At UC, four different structural modeling approaches were adopted for analysis. The current research focuses on the analysis of an in-house Sensorcraft joined wing model developed by the AFRL. This model is an equivalent representation of the actual 3-D joined wing model. The wing is idealized as a box structure consisting of shells, rods, beams, shear panels and concentrated masses. This box wing structure has the advantage of being computationally inexpensive over the full 3-D model, and has been optimized to minimize the deflections of the antennae equipment in the control surface of the wing. The fluid loads applied on the box-wing structure are obtained from a concurrent aerodynamic analysis for different mach numbers and angles of attack performed at UC.A modal representation is obtained for different oper (open full item for complete abstract)

Committee: Dr. Urmila Ghia (Advisor) Subjects: Engineering, Mechanical

Doctor of Philosophy (Ph.D.), University of Dayton, 2010, Aerospace Engineering

This study successfully described the mechanics of flapping hovering flight within the framework of conventional aerodynamics. Additionally, the theory proposed and supported by this research provides an entirely new way of looking at animal flapping flight. The mechanisms of biological flight are not well understood, and researchers have not been able to describe them using conventional aerodynamic forces. This study proposed that natural flapping flight can be broken down into a simplest model, that this model can then be used to develop a mathematical representation of flapping hovering flight, and finally, that the model can be successfully refined and compared to biological flapping data. This paper proposed a unique theory that the lift of a flapping animal is primarily the result of velocity across the cambered span of the wing. A force analysis was developed using centripetal acceleration to define an acceleration profile that would lead to a spanwise velocity profile. The force produced by the spanwise velocity profile was determined using a computational fluid dynamics analysis of flow on the simplified wing model. The overall forces on the model were found to produce more than twice the lift required for hovering flight. In addition, spanwise lift was shown to generate induceddrag on the wing. Induced drag increased both the model wing's lift and drag. The model allowed the development of a mathematical representation that could be refined to account for insect hovering characteristics and that could predict expected physical attributes of the fluid flow. This computational representation resulted in a profile of lift and drag production that corresponds to known force profiles for insect flight. The model of flapping flight was shown to produce results similar to biological observation and experiment, and these results can potentially be applied to the study of other flapping animals. This work provides a foundation on which to base further exploration a (open full item for complete abstract)

Committee: Aaron Altman PhD (Committee Chair); Kevin Hallinan PhD (Committee Member); Jose Camberos PhD (Committee Member); Timothy Fry PhD (Committee Member) Subjects: Animals; Biology; Engineering; Fluid Dynamics; Mechanical Engineering; Zoology

Master of Arts, The Ohio State University, 1923, Graduate School

Committee: Not Provided (Other) Subjects:

Master of Science, The Ohio State University, 2024, Aerospace Engineering

Various trailing-edge (TE) Coanda active flow control (AFC) actuator configurations were experimentally investigated in a propeller slipstream flow to simulate hover flight. This thesis will provide a comprehensive evaluation of the configuration factors—in terms of spanwise position and geometric parameters—which impact the aerodynamic and control authority performance of TE Coanda AFC actuators in propeller-driven flow with no freestream velocity. Two main types of TE Coanda AFC configuration experiments were conducted. The first type of testing involved varying the spanwise placement and size of TE AFC while maintaining constant internal geometry and circular Coanda profile shape with continuous slot blowing. The spanwise location testing's objectives were to determine the optimal Coanda AFC actuator location relative to the propeller slipstream and compare Coanda flow control effectiveness to that of a traditional deflection control surface. Two trailing-edge Coanda actuator sections of fixed spanwise length were designed, fabricated, and evaluated in terms of lift force and pitching moment generation at varying spanwise locations. Velocity profile measurements for this study for the case of no freestream flow indicated that the propeller slipstream is asymmetric over the NACA 0012 wing and contracts toward the side of the wing on which the propeller blade descends during rotation, where propeller downwash is experienced. This asymmetry indicated that there may be an optimum location for Coanda AFC actuators at the wing trailing edge which couple with momentum from the propeller in regions of peak slipstream velocity. The second type of testing involved varying TE AFC nozzle and surface profiles while maintaining constant spanwise location. These nozzles included both continuous and discrete slot blowing as well as sweeping jets. Surfaces investigated included circular, elliptical, and biconvex profiles. Each configuration was mounted to the trailing edge of (open full item for complete abstract)

Committee: Matthew McCrink (Committee Member); Jeffrey Bons (Advisor) Subjects: Aerospace Engineering

MS, University of Cincinnati, 2023, Engineering and Applied Science: Aerospace Engineering

Fixed-wing Unmanned Aerial Vehicles (UAVs) cannot fly at speeds lower than critical stall speeds. As a result, hovering during a potential collision scenario, like with rotary-wing UAVs, is impossible. Moreover, hovering is not an optimal solution for Collision Avoidance (CA), as it increases mission time and is innately fuel inefficient. This work proposes a decentralized Fuzzy Inference System (FIS)-based resolution algorithm that modulates the point-to-point mission path while ensuring the continuous motion of UAVs during CA. A simplified kinematic guidance model with coordinated turn conditions is considered to control the UAVs. The model employs a proportional-derivative control of commanded airspeed, bank angle, and flight path angle. The commands are derived from the desired path, characterized by airspeed, heading, and altitude. The desired path is, in turn, obtained using look-ahead points generated for the target point. The FIS aims to mimic human behavior during collision scenarios, generating modulation parameters for the desired path to achieve CA. Notably, it is also scalable, which makes it easy to adjust the algorithm parameters, as per the required missions, and factors specific to a given UAV. A genetic algorithm was used to optimize FIS parameters so that the distance traveled during the mission was minimized despite path modulation. The proposed algorithm was optimized using a pairwise conflict scenario. The effectiveness of the algorithm was evaluated through various pairwise conflict scenarios as well as a Monte Carlo simulation of random conflict scenarios involving multiple UAVs operating in a confined space. It was found that the overall number of collisions decreased by an average of 98% using the proposed optimized algorithm, thereby, supporting its effectiveness.

Committee: Donghoon Kim Ph.D. (Committee Chair); Daegyun Choi Ph.D. (Committee Member); Anoop Sathyan Ph.D. (Committee Member); Ou Ma Ph.D. (Committee Member); Kelly Cohen Ph.D. (Committee Member) Subjects: Aerospace Engineering

Master of Science (MS), Ohio University, 2023, Journalism (Communication)

This thesis examines the adherence of German and U.S.-American mainstream and right-wing online news platform's coverage of antifa protests to the protest paradigm. It further focuses on the portrayal of antifa protests and antifascist action in general, while considering societal differences as well as differences within the movements in both countries. This thesis applied a qualitative content analysis to N = 224 articles from eight media outlets. The analysis is structured along for key categories: framing as well as portrayal of the protest, portrayal of the protest group, and sourcing patterns. Results show common themes in the portrayal of antifa. All outlet types tend to demonize und delegitimize antifa protests and protest causes. German media does so in particular by heavily relying on the police as an official source. U.S. mainstream media is the only outlet type to sometimes include various other perspectives into their protest coverage, and to frequently provide contexts and political classifications of antifa protests. However, German mainstream and right-wing media generally show more similarities in their antifa coverage than German and U.S. mainstream media, especially in the portrayal of antifa. U.S. right-wing media stands out by employing frames that depict antifa values and protests as immoral, and members as anti-free speech and un-American. All outlet types' antifa protest coverage is marked by an emphasis on confrontations and on the measures needed to avert escalations, as well as by an overall negative tone towards antifa. Further, all media outlets point out the riot-like and in part anarchic characters of antifa protests and highlight property and violent crimes allegedly committed by antifa members during protests. All coverage adheres to the protest paradigm; mainstream media in both countries, however, employ more mixed frames, while right-wing media employ mainly marginalizing frames. Sympathetic and balanced re (open full item for complete abstract)

Committee: Aimee Edmondson (Committee Chair); Patrick Donges (Committee Member); Elizabeth Hendrickson (Committee Member) Subjects: Journalism

Master of Arts (MA), Bowling Green State University, 1960, Theatre

Committee: Norbert F. O'Donell (Advisor) Subjects: Theater

Master of Arts (MA), Bowling Green State University, 1960, Theatre

Committee: Norbert F. O'Donell (Advisor) Subjects: Theater

Master of Sciences, Case Western Reserve University, 2023, EMC - Aerospace Engineering

Proving the feasibility and overall efficiency of Flapping-Wing Micro Air Vehicles (FWMAVs) over other types of MAVs is vital for their advancement. Due to their complex aerodynamics and the difficulty of building accurate models of the flying animal, assessing the flight performance and efficiency of animals and FWMAVs mimicking those animals can be a challenging task. The research presented here investigates the hawk moth (Manduca Sexta L.) forewing as inspiration for designing an optimal wing for a moth-scale FWMAV using a surrogate modeling approach. The design of experiment (DOE) assesses the variation in aerodynamic lift-to-drag ratio due to variations in the wing geometry parameters. Using results from the experiment as training data, the trained surrogate model is a quadratic Support Vector Regression model that can rapidly evaluate the aerodynamic lift-to-drag ratio based on the wing geometry input parameters, thus identifying local extrema within the design space.

Committee: Kenneth Moses (Committee Chair); Roger Quinn (Committee Member); Bryan Schmidt (Committee Member) Subjects: Aerospace Engineering; Robotics

Master of Science (MS), Ohio University, 2022, Mechanical Engineering (Engineering and Technology)

Continuous curvature interception paths are needed to accurately return a fixed wing UAV with turn rate constraints back to a mission path after collision avoidance. Clothoid routes where curvature is linearly dependent to arc length are used to make multi-segment splines with continuous curvature, but require optimization to ensure that the path is of minimal length while meeting turn radius and rate constraints. The present work considers the problem of a UAV intercepting a path after leaving its planned mission route during collision avoidance. The first objective investigated a cost function to optimize a three segment clothoid return path to be of minimal length and meet turn radius and rate constraints. The second objective explored an optimization process for generating minimal length clothoid recovery paths and then evaluated their effectiveness by comparing to direct return methods with a simulated UAV. The impact of this work is enabling smooth and accurate path interception after collision avoidance with minimal length paths that minimize the time spent from a mission's planned path, providing more time to complete mission objectives.

Committee: Jay Wilhelm (Advisor); Sergio Ulloa (Committee Member); Brian Wisner (Committee Member); Robert Williams (Committee Member) Subjects: Mechanical Engineering

MS, University of Cincinnati, 2022, Engineering and Applied Science: Aerospace Engineering

The aim of this thesis is to expand the capabilities of Unmanned Aerial vehicles (UAV), by presenting an autonomous control algorithm and using a morphing box wing, which supports vertical and horizontal flight mode along with transition. This research work provides detailed description of the position and attitude controller for a hybrid morphing box wing UAV. Hybrid morphing wing UAV has ability to perform mission as both quadcopter and fixed-wing aircraft in efficient manner. Development of a single controller with ability to handle two different mode is discussed. Numerous work has been done to increase the application of conventional UAVs, but not very much work has been done in increasing the capability to efficiently combine and fly UAV in horizontal and vertical modes of flight. Hybrid morphing wing UAV is a structural enhancement of a conventional quadrotor that is attached with a wing structure which has morphing ability, and that helps to optimizes performance of UAV during flight. Maneuvering of a traditional quadcopter is controlled by varying the rotors speeds, where the rotation is clockwise for two diagonally opposite rotors and anti-clockwise for the other two rotors. The opposite rotation of rotors in quadcopter is used to control the yaw moment of the system. The quadcopters have two configurations in which they fly, namely '+' configuration and 'X' configuration. The '+' configuration have one rotating propeller on each side of the axes for rolling and pitching, whereas 'X' configuration have two counter rotating propeller on each side of the axes for rolling and pitching. The hybrid UAV proposed in this thesis, uses a quadcopter in 'X' configuration attached to the box wing. In order to improve the efficiency of the box wing during the whole flight regime, two approaches have been applied, first is the box wing in the shape of a nozzle and second is the morphing wing. Nozzle wing design (open full item for complete abstract)

Committee: Shaaban Abdallah Ph.D. (Committee Member); Rajnikant Sharma Ph.D. (Committee Member); Manish Kumar Ph.D. (Committee Member) Subjects: Aerospace Materials

Doctor of Philosophy, Miami University, 2022, Biology

Scientists have long been fascinated by morphological novelties, which at times seem to spring out of the ancestral form from no pre-existing structure (or structures, i.e. a complex novel trait). With molecular biology, it is relatively straightforward to work out the genes and regulatory interactions responsible for the proper development of these structures in extant species. However, what is more important from an evolutionary perspective (and more difficult to determine) is how a developmental gene regulatory network (GRN) is first pieced-together to create a novel structure. An intriguing possibility is that two or more ancestral GRNs may become cross-wired to drive the formation of a complex novel structure that is radically different from its origin tissues. The objective of this dissertation is to better understand how pre-existing GRNs from more than one origin tissue may combine to spark the origin of a complex morphological novelty, focusing on the origin of the insect wing. This chapter will provide background knowledge on the evolutionary impact of wing origin on the insects (Section 1.2), as well as relevant information on the development and morphology of the wings and proposed origin tissues (Section 1.3). This is followed by a brief history of the wing origin debate utilizing traditional comparative morphology (Section 1.4), a review of the major components of the wing GRN in the fruit fly (Section 1.5), and finally, a discussion on what evo-devo studies have discovered regarding the origin of the wing GRN (Section 1.6).

Committee: Yoshinori Tomoyasu (Advisor); Xin Wang (Committee Member); Michael Robinson (Committee Member); Jennifer Schumacher (Committee Member); Paul James (Committee Member) Subjects: Biology; Developmental Biology; Entomology; Evolution and Development