Aerospace Engineering Commons^™

Hybrid Physics-Informed Neural Networks For Dynamical Systems, Renato Giorgiani Do Nascimento

Electronic Theses and Dissertations, 2020-2023

Ordinary differential equations can describe many dynamic systems. When physics is well understood, the time-dependent responses are easily obtained numerically. The particular numerical method used for integration depends on the application. Unfortunately, when physics is not fully understood, the discrepancies between predictions and observed responses can be large and unacceptable. In this thesis, we show how to directly implement integration of ordinary differential equations through recurrent neural networks using Python. We leveraged modern machine learning frameworks, such as TensorFlow and Keras. Besides offering basic models capabilities (such as multilayer perceptrons and recurrent neural networks) and optimization methods, these frameworks offer …

Dynamics Within A Tunable Harmonic/Quartic Waveguide, Rudolph N. Kohn Jr., James A. Stickney

Space Dynamics Laboratory Publications

We present an analytical solution to the dynamics of a noninteracting cloud of thermal atoms in a cigar-shaped harmonic trap with a quartic perturbation along the axial direction. We calculate the first and second moments of position, which are sufficient to characterize the trap. The dynamics of the thermal cloud differ notably from those of a single particle, with an offset to the oscillation frequency that persists even as the oscillation amplitude approaches zero. We also present some numerical results that describe the effects of time-of-flight on the behavior of the cloud in order to better understand the results of …

Low-Cost Skewed Redundant Imu Configuration For State-Space Recovery In A Saturated Environment, Levi S. Hubbard

Graduate Theses, Dissertations, and Problem Reports (ETD)

Low-cost sensors for state space determination can be used successfully for ground vehicles, robots, unmanned aerial vehicles, and Internet-of-Things applications. When a high fidelity Inertial Measurement Unit (IMU) cannot be obtained for state space determination, low-cost sensors can be used to satisfactory standards, despite their limitations in capabilities, by using various implementation techniques. The research group was experimentally investigating state space information of an unstable flying vehicle for motion simulation validation. The high fidelity motion capture system would intermittently lose track of the flight vehicle which lost critical flight data.

The goal was to determine the potential of low-cost off-the-shelf …

Improving The Biological Control Of Persicaria Perfoliata (Polygonaceae) Using Rhinoncomimus Latipes Korotyaev (Coleoptera: Curculionidae), Jaewon Kim

Graduate Theses, Dissertations, and Problem Reports (ETD)

Persicaria perfoliata (L.) H. Gross (Polygonaceae; Mile-a-minute weed) is a rapid-growing invasive vine introduced from eastern Asia to northeastern United States in the 1930s. This vine has been invaded in disturbed areas and reforestation sites in 15 states in the U.S. and forms dense, monocultural patches that may inhibit natural forest regeneration. To control this weed, a host-specific biocontrol agent, Rhinoncomimus latipes Korotyaev (Coleoptera: Curculionidae) has been released in the P. perfoliata invaded states in the U.S. during the past 15 years. Currently, R. latipes is released by hand to the invaded area where the presence of the weed is …

Characterizing Premixed Syngas Combustion In Micro-Channels, Sunita Pokharel

Graduate Theses, Dissertations, and Problem Reports (ETD)

Increasing demands in the next-generation portable power-generation devices such as unmanned aerial vehicles (UAV), microsatellite thrusters, micro-chemical reactors and sensors calls for fuels with high specific energy and low emissions to meet the current demand of green energy. Fuel-lean synthesis gas (syngas) meets both these requirements exhibiting a promising route to a clean and green environment. Thus, it is of critical importance to characterize syngas combustion and understand its properties in the micro-combustion industry. In addition to complicated flame dynamics in microscale systems, varying the syngas-fuel mixture composition as well as the boundary conditions and geometry of a combustor significantly …

Aeroelasticity Of Composite Plate Wings Using Hsdt And Higher-Order Fem, Justin A. Haught

Graduate Theses, Dissertations, and Problem Reports (ETD)

The aeroelasticity of composite wings is becoming an increasingly researched topic in aircraft design, as designers continue to replace aluminum alloy components with those made of composite materials because of their favorable strength-to-weight ratio, fatigue characteristics, and corrosion resistance. Additionally, the bending-torsion coupling exhibited by composite laminates readily allow for the aeroelastic optimization of an aerodynamic structure through the process of aeroelastic tailoring. Wings made of composites materials, however, are more vulnerable to shear deformation.

The objective of the present research is to study the divergence and flutter characteristics of composite plate wings using a higher-order shear deformation theory (HSDT) …

Synthesis Of Graphene Using Plasma Etching And Atmospheric Pressure Annealing: Process And Sensor Development, Andrew Robert Graves

Graduate Theses, Dissertations, and Problem Reports (ETD)

Having been theorized in 1947, it was not until 2004 that graphene was first isolated. In the years since its isolation, graphene has been the subject of intense, world-wide study due to its incredibly diverse array of useful properties. Even though many billions of dollars have been spent on its development, graphene has yet to break out of the laboratory and penetrate mainstream industrial applications markets. This is because graphene faces a ‘grand challenge.’ Simply put, there is currently no method of manufacturing high-quality graphene on the industrial scale. This grand challenge looms particularly large for electronic applications where the …

Terrain Aware Traverse Planning For Mars Rovers, Gabrielle Hedrick

Graduate Theses, Dissertations, and Problem Reports (ETD)

NASA is proposing a Mars Sample Return mission, to be completed within one Martian year, that will require enhanced autonomy to perform its duties faster, safer, and more efficiently. With its main purpose being to retrieve samples possibly tens of kilometers away, it will need to drive beyond line-of-sight to get to its target more quickly than any rovers before. This research proposes a new methodology to support a sample return mission and is divided into three compo-nents: map preparation (map of traversability, i.e., ability of a terrain to sustain the traversal of a vehicle), path planning (pre-planning and replanning), …

Satellite Constellation Deployment And Management, Joseph Ryan Kopacz

Electronic Theses and Dissertations

This paper will review results and discuss a new method to address the deployment and management of a satellite constellation. The first two chapters will explorer the use of small satellites, and some of the advances in technology that have enabled small spacecraft to maintain modern performance requirements in incredibly small packages.

The third chapter will address the multiple-objective optimization problem for a global persistent coverage constellation of communications spacecraft in Low Earth Orbit. A genetic algorithm was implemented in MATLAB to explore the design space – 288 trillion possibilities – utilizing the Satellite Tool Kit (STK) software developers kit. …

Applications Of Drones In Atmospheric Chemistry, Travis J. Schuyler

Theses and Dissertations--Chemistry

The emission of greenhouse gases (GHGs) has changed the composition of the atmosphere during the Anthropocene. A major technical and scientific challenge is quantifying the resulting fugitive trace gas fluxes under variable meteorological conditions. Accurately documenting the sources and magnitude of GHGs emission is an important undertaking for discriminating contributions of different processes to radiative forcing. Therefore, the adverse environmental and health effects of undetected gas leaks motivates new methods of detecting, characterizing, and quantifying plumes of fugitive trace gases. Currently, there is no mobile platform able to quantify trace gases at altitudes(UASs), or drones, can be deployed on-site in …

Thermal / Structural Analysis Of The Hb 650 Thermal Shield, Gerald J. Smith

Graduate Research Theses & Dissertations

Fermilab’s PIP-II project’s superconducting linear accelerator (Linac) will drive the next generation of particle accelerators through a revolution in beam intensity. Key to beam intensification are the high efficiencies of niobium-tin superconducting radiofrequency (SRF) cavities operating at cryogenic temperatures near 5 Kelvin. A multifaceted approach is employed to achieve and maintain the extreme temperature. Vacuum provides the first barrier to thermal convection. Physical thermal intercept zones further isolate the exterior shell vacuum vessel at 300 Kelvin from the supercooled beamline. The first thermal intercept lies just inside the exterior vacuum vessel forming the 40 Kelvin zone. This 40K thermal shield …

Active Fault-Tolerance Of The Unmanned Aerial Vehicle Automatic Control Systems, Vuong Anh Trung, Nguyen Van Thinh, Nguyen Duc Thanh, Nguyen Quang Vinh, Tran Thuan Hoang

International Journal of Aviation, Aeronautics, and Aerospace

This paper presents an introductory overview of principles of the three-layer hierarchy of active fault-tolerance, providing, determination of the fault type with as many details as enough to get recoverable fault reason and failure toleration by flexible redundancy using; the conception of active fault-tolerant control in abnormal modes is described. Developed models and methods of a systematic approach to fault tolerance in the direction of the effective use of the signal, parametric and structural redundancies and selection of parrying tools. Performed experimental researches of the unmanned aerial vehicle (UAV) automatic control systems (ACS).

Adaptive Filtration Of The Uav Movement Parameters Based On The Aoa-Measurement Sensor Networks, Igor Tovkach, Serhii Zhuk

International Journal of Aviation, Aeronautics, and Aerospace

Currently, the urgent task is to assess the small-sized maneuvering UAVs movement parameters. The location of an unknown UAV as a radio source can be determined using AoA measurements of the wireless sensor network. To describe the movement of a maneuvering UAV, a model is used in the form of a dynamic system with switching in discrete time. The values of switching variable determine type of UAV movement. To synthesize trajectory filtering algorithms, the Markov property of the extended process is used, which includes a vector of UAV movement parameters and a switching variable. The optimal trajectory filtering algorithm describes …

Magnetic Control Of Transport Of Particles And Droplets In Low Reynolds Number Shear Flows, Jie Zhang

Doctoral Dissertations

“Magnetic particles and droplets have been used in a wide range applications including biomedicine, biological analysis and chemical reaction. The manipulation of magnetic microparticles or microdroplets in microscale fluid environments is one of the most critical processes in the systems and platforms based on microfluidic technology. The conventional methods are based on magnetic forces to manipulate magnetic particles or droplets in a viscous fluid.

In contrast to conventional magnetic separation method, several recent experimental and theoretical studies have demonstrated a different way to manipulate magnetic non-spherical particles by using a uniform magnetic field in the microchannel. However, the fundamental mechanism …

Applications Of Information Theory In Filtering And Sensor Management, Matthew James Gualdoni

Doctoral Dissertations

“A classical sensor tasking methodology is analyzed in the context of generating sensor schedules for monitoring resident space objects (RSOs). This approach, namely maximizing the expected Kullback-Leibler divergence in a measurement update, is evaluated from a probabilistic perspective to determine the accuracy of the conventional approach. In this investigation, a newdivergence-based approach is proposed to circumvent themyopic nature of the measure, forecasting the potential information contribution to a time of interest and leveraging the system dynamics and measurement model to do so. The forecasted objective exploits properties of a batch measurement update to frequently exhibit faster optimization times when compared …

Fabrication And Characterization Of Multifunctional Composites, Aditya R. Thakur

Doctoral Dissertations

“This study details the research to facilitate fabrication and characterization of novel structural composites reinforced with carbon fibers. Across industries, materials with high performance-to-weight ratio are sought after. Using carbon fibers as secondary phases in these proposed composites, specific characteristics can be tailored in these materials to manufacture strong, lightweight, high performance structures. The first part of the research focused on the improvement in the mechanical properties of the composites using carbon fiber reinforcement. As a part of this study, toughened ceramic composites with predictable failure patterns were produced using carbon fiber inclusions. A closed-form analytical model was developed to …

Finite Time Suboptimal Control Design Of Nonlinear Systems With Θ-D Technique And Implementation To Aerospace Applications, Jie Yao

Doctoral Dissertations

“A finite time suboptimal control strategy (named θ - D approximated algorithm) was proposed in this study, which can provide the control engineers with a novel effective and efficient design tool from the finite time optimal perspective. Based on the framework of this proposed method, the original nonlinear dynamics were formulated in pseudo-linear form, and the performance index was denoted by a linear quadratic regulator prototype in this research. After that, the approximated solutions to intractable Hamilton-Jacobi-Bellman (HJB) equation were acquired by putting vanishing perturbation terms into the performance index. By tuning the parameters in perturbation terms, semi-global stability and …

Impact Of Turbulence Models And Shape Parameterization On Robust Aerodynamic Shape Optimization, Aslihan Vuruskan

Doctoral Dissertations

"Aerodynamic design optimization is typically performed at fixed flight conditions, without considering the variation and uncertainty in operating conditions. The objective of robust aerodynamic optimization is to design an aerodynamic configuration, which will keep its optimum performance under varying conditions such as the speed of aircraft. The primary goal of this study was to investigate the impact of turbulence models used in RANS simulations on the 2-D airfoil and 3-D wing designs obtained with gradient-based deterministic and robust optimization in transonic, viscous, turbulent flows. The main contribution of this research to the aerodynamic design area was to quantify the impact …

Wind Release Mechanical Sun Tracker, Tyler Andrus, Brady Fisher, Jt Gibson, Cynthia Rigby, Derek Smith

Mechanical and Aerospace Engineering

• Solar panel sun tracking system that releases solar panels to orient to wind flow in high wind conditions

• Operates on a single rotational motor

• Designed to be lightweight and portable

Afrl Downed Airman Recovery System, Daniel Cornia, James Bennett, Matthew Halton, Matthew Bennett, Brandon Haws, Tyson Compton, Jacob Needham, Daniel Spreier, Thory Van Dyke

Mechanical and Aerospace Engineering

For the 2020 Air Force Research Laboratory design competition, teams were challenged to develop a system to assist Combat Search and Rescue (CSAR) in recovering a downed pilot in contested waters.

In the event of a pilot ejecting from their aircraft, a GPS beacon notifies CSAR of the pilot’s approximate location. During the rescue operation, a swimmer from a CSAR crew enters the water and assists the isolated person (IP) to use rescue equipment.

The current procedure exposes an additional person to hazards and increases IP extraction time. The additional required personnel and setup time increases mission risk.

USU’s student …