Mechanical Response Of Triply Periodic Minimal Surface Gyroid Structures Under Combined Loading,
2025
Air Force Institute of Technology
Mechanical Response Of Triply Periodic Minimal Surface Gyroid Structures Under Combined Loading, Jay B. Patel
Theses and Dissertations
This work explored combined tensile and torsional loads applied to additively manufactured Inconel 718 specimens employing Triply Periodic Minimal Surface (TPMS) structures. The gyroid TPMS unit cell was selected with two variations of cylindrical cell maps, a rectangular cell map, and a spherical cell map. All four variants were tested in an axial-torsion test frame at room temperature using equal parts of vertical and angular displacement control until failure. The combined loading in these tests utilized tension and torsion. The data from the tests were compared to finite element analysis (FEA) models to visualize when yielding was predicted. Finally, the …
Graph Neural Network-Based Uav Coverage Planning For Robust And Efficient 3d Environments,
2025
Air Force Institute of Technology
Graph Neural Network-Based Uav Coverage Planning For Robust And Efficient 3d Environments, Gal Tsfaty
Theses and Dissertations
This thesis addresses the challenge of generating optimized UAV waypoints for complete coverage of complex 3D environments, utilizing graph-based computational techniques. The proposed framework replaces computationally intensive steps—triangulation and three-coloring—within the Vantage Waypoint Set Generation Algorithm (VWSGA) pipeline with Graph Neural Networks (GNNs). By learning structural patterns, the GNN achieves scalable and robust triangulation and node classification, enabling enhanced coverage planning in irregular geometries. A novel penalty mechanism ensures alignment with graph structure during adjacency prediction. Experimental results demonstrate the effectiveness of GNNs in balancing accuracy, computational efficiency, and adaptability, advancing UAV coverage optimization.
Autonomous Vehicle Path Planning Under Uncertainty,
2025
Air Force Institute of Technology
Autonomous Vehicle Path Planning Under Uncertainty, Madison C. Gillan
Theses and Dissertations
Autonomous vehicles are increasingly being deployed for use in high-stakes and uncertain environments where safe and efficient navigation is critical. In these scenarios, traditional path planning approaches, which rely primarily on deterministic models and fixed assumptions, fall short due to the inherent uncertainty of dynamic threats, sensor inaccuracies, and incomplete information. This research addresses these challenges by developing a novel path-planning methodology that combines the Chance-Constrained Rapidly Exploring Random Tree* (CC-RRT*) algorithm with a probabilistic risk assessment heuristic. This method models uncertainty in sensor detection zones, obstacles in the environment, and the Autonomous Vehicle itself, which allows for uncertainty during …
Commercial Satellite Payload Trends,
2025
Air Force Institute of Technology
Commercial Satellite Payload Trends, Alexander B. Krawietz
Theses and Dissertations
This thesis examines the evolving trends in commercial satellite payloads with an emphasis on mass, operating power, and project duration overall and across different payload types, serving as a benchmark for Department of Defense (DoD) leaders to compare against private industry advancements. Utilizing a comprehensive dataset of open-source commercial satellite data, this study identifies significant trends that could influence cost estimation, schedule estimation, and satellite design. The analysis not only highlights the technological progression over several decades but also provides a comparative insight into how the United States and China are positioned in their race for space dominance. Beyond detecting …
Visual Segmentation For Autonomous Aircraft Landing On Austere Runways,
2025
Air Force Institute of Technology
Visual Segmentation For Autonomous Aircraft Landing On Austere Runways, Alissa M. Owens
Theses and Dissertations
Autonomous aircraft must land without human intervention, but existing methods rely on GPS or marked runways, which may be unavailable in austere environments. This paper presents a vision-based approach using semantic segmentation to detect runways and estimate aircraft pose by comparing camera and satellite imagery. We detail the model’s training and demonstrate its effectiveness with simulated and real UAV data.
Universal Model Based Systems Engineering Rendezvous And Proximity Operations Mission Planner,
2025
Air Force Institute of Technology
Universal Model Based Systems Engineering Rendezvous And Proximity Operations Mission Planner, Thomas J. Kelly
Theses and Dissertations
This thesis addresses the fragmentation and inefficiencies in current Rendezvous and Proximity Operations (RPO) mission planning by developing an integrated Model-Based Systems Engineering (MBSE) framework. The research explores the design and implementation of RPO missions using System Modeling Language (SysML) and Matlab-based physics simulation to improve mission planning processes. Key objectives include the standardization of mission requirement characterization, the development of evaluation criteria for mission plans, and the implementation of iterative design methods to refine RPO strategies. The study leverages the Hill-Clohessy-Wiltshire (HCW) equations for initial mission planning, incorporating rigid-body attitude control with properties generated from the physical description, and …
Fatigue Behavior Of Two Advanced C/Sic Composites At 1200°C In Air,
2025
Air Force Institute of Technology
Fatigue Behavior Of Two Advanced C/Sic Composites At 1200°C In Air, Conner A. Adams
Theses and Dissertations
High-temperature tension-tension fatigue behavior of two advanced carbon/silicon carbide (C/SiC) ceramic matrix composites (CMCs) was investigated. Both composites were reinforced with T300 carbon fibers. Laminated carbon fiber preforms consisted of 24 plies of plain weave fabric in a 0/90 layup. The first composite, C/CVI-SiC, was processed by chemical vapor infiltration (CVI) of SiC into the fiber preform. Prior to the CVI process, the fiber preforms were coated with a duplex pyrolytic carbon and boron carbide fiber coating to create a weak fiber- matrix interphase. The second composite, C/HYPR-SiC, was also processed via CVI, but had an oxidation inhibited matrix comprising …
Adiabatic And Overall Effectiveness Superposition Theory For Upstream Phantom Cooling On A Film Cooled Leading Edge,
2025
Air Force Institute of Technology
Adiabatic And Overall Effectiveness Superposition Theory For Upstream Phantom Cooling On A Film Cooled Leading Edge, Nathaniel J. Stout
Theses and Dissertations
Film cooling experimentation aims to improve the cooling performance while minimizing the amount of coolant flow redirected from the compressor. The coolant flow that is used for film cooling reduces the maximum thrust any gas turbine engine can produce. Finding creative ways to improve cooling performance without increasing the amount of coolant used, like phantom cooling, is essential for the gas turbine industry to improve engine performance while increasing turbine components’ lifespan. Phantom cooling refers to any secondary cooling effect that propagates downstream from its original cooling application to cool subsequent turbine components. Phantom cooling is actively gaining more attention …
Heterogeneous Boid Swarm Performance Under Environmental And Neighbor Communication Link Variability,
2025
Air Force Institute of Technology
Heterogeneous Boid Swarm Performance Under Environmental And Neighbor Communication Link Variability, Jonathan C. Oxborrow
Theses and Dissertations
Artificial swarms are of growing interest in numerous fields and use cases. As their utilization increases drones and robots with different capabilities will be required to coordinate for task completion thus creating heterogeneous swarms. Swarm individuals generally communicate with all neighbors inside their sensor range generating a significant amount of message traffic. Previous research of a heterogeneous group in a non-physical environment has shown that restricting communication to only one neighbor of each different capability maintained performance. This work applies that finding to a heterogeneous boid swarm with the addition of varied environmental conditions. The swarm is comprised of three …
Fatigue Behavior Of An Advanced Sic/Sic Composite With An Array Of Small Cooling Holes At 1200°C,
2025
Air Force Institute of Technology
Fatigue Behavior Of An Advanced Sic/Sic Composite With An Array Of Small Cooling Holes At 1200°C, Tess K. Panchyshyn
Theses and Dissertations
Tension-tension fatigue behavior of an advanced melt-infiltrated (MI) silicon carbide/silicon carbide (SiC/SiC) composite was evaluated, and basic tensile properties measured, at 1200°C in laboratory air. The composite consists of a melt-infiltrated SiC matrix reinforced with laminated Hi-Nicalon Type-S fibers woven in a 5-harness satin weave. The Hi-Nicalon-S fiber preforms were coated with a boron nitride (BN) fiber coating by chemical vapor infiltration (CVI). The melt-infiltrated matrix was consolidated by combining CVI-SiC with SiC particulate slurry and molten silicon infiltration. The finished ceramic matrix composite (CMC) had a fiber volume fraction of 33%. Additionally, the effect of multiple small holes on …
Improving Smartphone Gnss Jammer Localization With Cloud-Based Environmental Occlusion Modeling,
2025
Air Force Institute of Technology
Improving Smartphone Gnss Jammer Localization With Cloud-Based Environmental Occlusion Modeling, Glenn H. Jones
Theses and Dissertations
The advancement of Global Navigation Satellite System (GNSS) technology in modern smartphones has made these devices pervasive in both civilian and military applications. Although smartphone GNSS chipsets are more susceptible to jamming and spoofing than military grade hardware, smartphone networks offer an underutilized opportunity to detect and mitigate threats to position, navigation, and timing (PNT) services essential to the Department of Defense (DoD) and civilian first responders. Traditional methods for geolocating ground-based jamming sources using smartphone GNSS often fail in environments with dense vegetation or significant occlusions, resulting in substantial localization errors.
A Multi-Objective Reinforcement Learning Framework For Title Autonomous On-Orbit Inspections,
2025
Air Force Institute of Technology
A Multi-Objective Reinforcement Learning Framework For Title Autonomous On-Orbit Inspections, Austin C. Reynolds
Theses and Dissertations
The rapidly evolving landscape of space operations necessitates dynamic and autonomous systems to address complex challenges such as Resident Space Object (RSO) inspections. This research explores the application of a Multi-Objective Reinforcement Learning (MORL) framework to rendezvous and proximity operations (RPO), enabling agents to balance conflicting objectives like time efficiency, fuel conservation, and information gain. Unlike traditional reinforcement learning, MORL allows dynamic reweighting of objectives without retraining, offering adaptability and efficiency in multi-objective environments. The study demonstrates MORL's capabilities through custom 2D and 3D simulations of Hill-Clohessy-Wiltshire (HCW) environments and comparing its performance to traditional RL in RPO scenarios. Tasks …
Lethality And Survivability Of Autonomous Self-Sensing Uavs,
2025
Air Force Institute of Technology
Lethality And Survivability Of Autonomous Self-Sensing Uavs, Jeffrey T. Wilson
Theses and Dissertations
Unmanned Aerial Vehicles (UAVs) have seen increased usage over the past two decades during the Global War on Terrorism (GWOT), operating in low-risk environments against dispersed enemies with minimal counter-drone capabilities. However, as the U.S. military shifts focus to Multi-Domain Operations (MDO) and Large Scale Combat Operations (LSCO), UAVs face significantly higher risks, including frequent and successful attacks, as well as the exploitation of their technology. Battle damage assessment (BDA) is not new; however, autonomous self-assessment by UAVs represents a novel advancement. Currently, UAV BDA relies on manual inspection, requiring approximately eight hours per drone. By adopting self-sensing technology, UAVs …
Utility Of Self-Sensing Damage Technology Through A2/Ad Drone Combat Simulation,
2025
Air Force Institute of Technology
Utility Of Self-Sensing Damage Technology Through A2/Ad Drone Combat Simulation, Sidhanth Venkatasubramaniam
Theses and Dissertations
Since the introduction of the first unmanned aerial vehicle (UAV), UAVs have consistently improved in capability and versatility. The ability to perform military operations without the risk of losing human life is crucial for the United States military. The trade-off for this versatility is cost, and several ongoing research efforts are being made to improve UAV mission success and the lifespan of UAVs. An area of research that falls under the categories mentioned is self-damage detection. The Air Force Research Laboratories (AFRL) are developing a capability to enable a UAV to assess airframe damage, enabling real-time determination of damage potentially …
Proof Of Concept: Using Uas Technology To Accomplish Aerial Roof Inspections,
2025
Air Force Institute of Technology
Proof Of Concept: Using Uas Technology To Accomplish Aerial Roof Inspections, Madison R. Fanning
Theses and Dissertations
With the growing use of simulation across industries, the digital twin remains an underexplored research area, particularly in emergency management and response. Its real-time updating capability is often overlooked due to the misconception that "digital twin" is merely a complex term for simulation. This paper highlights its distinctiveness through an evasion exercise involving two independent entities in a collocated environment. Using a highly integrated virtual environment (HIVE) and internet of things (IoT) devices, we link the physical system with an analytical simulation, demonstrating the impact of lag times in high-pressure scenarios. The computational model leverages agent-based modeling (ABM) and discrete-event …
Best Estimate Reconstruction Of The Control Profile For A Maneuvering Reentry Vehicle,
2025
Air Force Institute of Technology
Best Estimate Reconstruction Of The Control Profile For A Maneuvering Reentry Vehicle, Justin R. Evans
Theses and Dissertations
Astrodynamic reentry is an increasingly important flight regime as countries around the world develop new spacecraft and weapons. A design of interest is that of hypersonic glide vehicles with the ability to maneuver in the atmosphere. As these vehicles become more common across the world, it has become advantageous to track foreign reentry tests in order to determine capabilities. While current observation techniques may allow position and velocity to be tracked across the trajectory, orientation of the vehicle is not always observable. The ability to find vehicle orientation across time gives insight into the performance characteristics of the vehicle. This …
Extension Of The Circular Restricted N-Body Problem (Crnbp) To Varying Multi-Body Gravitational Systems,
2025
Air Force Institute of Technology
Extension Of The Circular Restricted N-Body Problem (Crnbp) To Varying Multi-Body Gravitational Systems, Annika J. Gilliam
Theses and Dissertations
Multi-body dynamical models are a valuable tool used to examine certain aspects of spacecraft orbital mechanics by applying assumptions to restrict the problem. The Circular Restricted Three-Body Problem (CR3BP), one of these dynamical models, has been examined extensively in the last few decades; however, this model is not sufficient in the case of more than two massive celestial bodies gravitationally affecting a spacecraft. A novel model called the Circular Restricted N-Body Problem (CRNBP) is studied in this research as an alternative to the traditional CR3BP where necessary. A variety of systems are examined in this thesis, including the Jovian, Saturnian, …
Approximating Three-Body Trajectories With A Knot Theory Inspired Model For Orbit Generation And Determination,
2025
Air Force Institute of Technology
Approximating Three-Body Trajectories With A Knot Theory Inspired Model For Orbit Generation And Determination, Mason R. Mill
Theses and Dissertations
This thesis explores a novel approach to approximating three-body trajectories using a knot theory-inspired model for orbit generation and determination. Traditional methods for solving the Circular Restricted Three-Body Problem (CR3BP) rely on numerical integration and correction schemes to generate trajectories, often requiring iterative refinements. This research investigates the application of knot theory principles—such as torus knots, Alexander polynomials, and Reidemeister moves—to categorize and model complex orbital trajectories in the CR3BP. By leveraging these mathematical tools, the study aims to enhance trajectory prediction, orbit determination, and mission planning for spacecraft operating in the cislunar environment. The results demonstrate that knot theory …
Analyzing And Mapping Hypersonic Cruise Vehicle Maneuvers,
2025
Air Force Institute of Technology
Analyzing And Mapping Hypersonic Cruise Vehicle Maneuvers, Kyle T. Monsma
Theses and Dissertations
This thesis develops a computational framework for analyzing the stability, control, and maneuverability of hypersonic cruise vehicles using surrogate modeling and trajectory propagation techniques. A polynomial ridge regression approach is implemented to create a continuous aerodynamic model from discrete force-moment data, enabling rapid stability and control assessments across Mach and altitude ranges. Vinh’s equations of motion are utilized to account for Earth’s curvature and gravitational effects, refining trajectory analysis for maneuver feasibility studies. Energy maneuverability diagrams, turn rate charts, and short-period stability metrics are generated to visualize flight performance constraints and dynamic stability characteristics. The results highlight the impact of …
Investigation Of The Convective Heat Transfer Driving Potential For Hypersonic Flows,
2025
Air Force Institute of Technology
Investigation Of The Convective Heat Transfer Driving Potential For Hypersonic Flows, Roderick A. Mills
Theses and Dissertations
Accurately determining adiabatic wall temperature is critical for characterizing surface heating in hypersonic flows. The differences between adiabatic wall temperature and stagnation temperature for Mach 6 flow are examined. A two-dimensional explicit finite difference scheme was developed to analyze heat transfer within an angled wedge and to assess the applicability of the classical semi-infinite solid solution to the Fourier Heat Equation for estimating adiabatic wall temperature and convective heat transfer coefficients. Experimental surface temperature data were extracted from infrared thermography obtained during Mach 6 wind tunnel tests, and the semi-infinite solid solution was applied to estimate the adiabatic wall temperature. …
