Engineering Commons^™

Mixed-Input Learning For Multi-Point Landing Guidance With Hazard Avoidance Part Ii: Learning-Based Guidance Algorithm, Sixiong You, Chaoying Pei, Vinay Kenny, Ran Dai, Jeremy R. Rea

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This paper investigates the three-dimensional (3D) multi-point landing guidance (MLG) problem with hazard avoidance by developing a mixed-input learning-based method to achieve precise and fuel-efficient planetary landing in future Mars missions. Specifically, we aim to find a safe, fuel-efficient landing point and generate a fuel-optimal trajectory simultaneously in real-time. First, by introducing binary variables, the MLG problem is formulated as an optimal control problem with quadratic constraints. Then, by formulating the Hamiltonian function, the necessary conditions of optimality for the MLG problem are obtained, where the critical parameters are identified to represent the complete optimal solution. After that, to find …

Feature-Based Learning For Optimal Abort Guidance, Vinay Kenny, Sixiong You, Godfrey Hendrix, Chaoying Pei, Roha Gul, Ran Dai, Jeremy R. Rea

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The abort mission refers to the mission where the landing vehicle needs to terminate the landing mission when an anomaly happens and be safely guided to the desired orbit. This paper focuses on solving the time-optimal abort guidance (TOAG) problem in real-time via the feature-based learning method. First, according to the optimal control theory, the features are identified to represent the optimal solutions of TOAG using a few parameters. After that, a sufficiently large dataset of time-optimal abort trajectories is generated offline by solving the TOAG problems with different initial conditions. Then the features are extracted for all generated cases. …

Distributed Optimization For Rank-Constrained Semidefinite Programs, Chaoying Pei, Sixiong You, Chuangchuang Sun, Ran Dai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This letter develops a distributed optimization framework for solving the rank-constrained semidefinite programs (RCSPs). Since the rank constraint is non-convex and discontinuous, solving an optimization problem with rank constraints is NP-hard and notoriously time-consuming, especially for large-scale RCSPs. In the proposed approach, by decomposing an unknown matrix into a set of submatrices with much smaller sizes, the rank constraint on the original matrix is equivalently transformed into a set of constraints on the decomposed submatrices. The distributed framework allows parallel computation of subproblems while requiring coordination among them to satisfy the coupled constraints. As the scale of every subproblem solved …

Orbital Stabilization Of Underactuated Systems Using Time Period Regulation, Nilay Kant, Ranjan Mukherjee

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A new approach to orbital stabilization of under-actuated systems with one passive degree-of-freedom (DOF) is presented. Virtual holonomic constraints are enforced using partial feedback linearization; this results in a dense set of periodic orbits on a constraint manifold. Every orbit on the constraint manifold is associated with a unique time-period. A desired orbit is selected, and the impulse controlled Poincaré map (ICPM) approach is utilized to stabilize the orbit by regulating the time-period. By treating the time period as the output, it is possible to design a dead-beat controller that achieves orbital stabilization in a single time-step. The effectiveness of …

Exploring Additive Manufacturing In A Space Environment - A Capstone Design Project Experience, Zain Zafar Khan, Zachary Alan Sobelman, Sharanabasaweshwara Asundi

Mechanical & Aerospace Engineering Faculty Publications

The employment of additive manufacturing in the non-standard environments like space, ships, or submarines has the potential to be an advanced utility not only in the pre-flight production of aerospace components and structures, but also for the onboard manufacturing of components and tools necessary for future space missions. For example, the ability to produce tools and structural components on the International Space Station can provide the space community the opportunity to make repairs and upgrades to the space station without wasting time and resources transporting such materials through additional missions. Additive manufacturing would allow for space missions to use on …

A Numerical Analysis Of Shock Angles From Inward Turning Axisymmetric Flows, William L. Hilal

Honors Undergraduate Theses

Detonation-based propulsion systems are known for their high efficiency and energy release when compared to deflagrative systems, making them an ideal candidate in hypersonic propulsion applications. One such engine is the Oblique Detonation Wave (ODW) engine, which has a similar architecture to traditional scramjets but shortens the combustor and isolator to an anchored ODW after fuel injection.

Previous research has focused on using a two-dimensional wedge to induce an ODW while limiting total losses through the combustor. In this configuration, a two-dimensional wedge-based architecture entails a rectangular duct, limiting potential inlet design and increasing overall skin friction. However, an inward-turning …

An Optimization Study Of Small-Scale Propeller Blade, Fahad M. Nabid

Honors Undergraduate Theses

This research paper aims to investigate the optimization of smaller propeller blades to achieve maximum efficiency by studying the effect of the twist angle on reducing drag, increasing thrust, and preventing rapid wear on the blade. Inefficient propellers consume a significant amount of energy, particularly during low-speed flights. The low Reynolds number regime challenges aviation engineers to design propellers with the highest possible efficiency to minimize energy losses. The primary objective of this thesis is to optimize smaller propeller blade shapes to enable them to produce maximum efficiency. The advanced ratio of a propeller blade heavily influences the blade's performance …

Hypersonic Scramjet Inlet Development For Variable Mach Number Flows, Zachary P. White

Honors Undergraduate Theses

Hypersonic propulsion has become an increasingly important research field over the past fifty years, and subsequent interest in propulsion systems utilizing supersonic combustion has emerged. Air-breathing engines are desirable for such applications as hypersonic flight vehicles would not need to carry an oxidizer. Therefore, hypersonic air-breathing propulsion systems require an inlet with high mass capture and compressive efficiency. The present work seeks to outline the development and validation of a novel design tool for producing air inlet designs for hypersonic vehicles at variable flight conditions. A Busemann inlet was chosen for its high compressive efficiency, geometric flexibility, and existing experimental …

The Development Of Computational Models For Melting-Solidification Applications Using The Volume-Of-Fluid Method, Brendon Cavainolo

Electronic Theses and Dissertations, 2020-2023

Fluids-related issues in the Aerospace industry are often multiphase in scope. Numerical modeling, such as computational fluid dynamics, is used to describe these problems, as they are difficult or impossible to describe analytically. This research uses computational fluid dynamics to describe multiphase problems related to melting-solidification and particle impingement. Firstly, a numerical model was established that uses the Volume-of-Fluid method to resolve a melting/solidifying particle. This model was verified against experiments and simplified analytical models, and a mesh independence study was done to ensure the results were independent of the mesh sizing. Next, the model was applied to two separate …

Oxidation Layer Formation On Aluminum Substrates With Surface Defects Using Molecular Dynamics Simulation, Emmanuel Olugbade, Hiep Pham, Yuchu He, Haicheng Zhou, Chulsoon Hwang, Jonghyun Park

Electrical and Computer Engineering Faculty Research & Creative Works

Aluminum Oxide Layer Affects the Integrity of Electrical Contact and Can Contribute Adversely to Passive Intermodulation (PIM) Behavior in Radio Frequency (RF) Devices, necessitating a Need for Understanding its Formation Mechanism and Realistic Estimation of its Thickness. using ReaxFF Molecular Dynamics Simulation Technique, This Study Investigated the Impact of Surface Defects on Aluminum Oxide Layer Formation. Results Reveal that Crystallographic Orientation Did Not Affect the Kinetics of Oxidation Process of Aluminum. However, the Reaction Kinetics Increased Significantly with Surface Inhomogeneities Such as Cracks, Scratches, and Grain Boundaries. a Non-Uniform Oxide Layer with Thickness Variation in the Range of 72-77% Was …

A Computational Fluid Dynamic Analysis Of Oxyacetylene Combustion Flow For Use In Material Response Boundary Conditions, Craig Meade

Theses and Dissertations--Mechanical and Aerospace Engineering

Oxyacetylene torches are used in the aerospace industry and research to test thermal protection system materials (TPS) due to their high flame temperatures and high heat flux capabilities. The purpose of this work is to determine a combustion model to accurately simulate the high temperature flow of an oxyacetylene torch. The flow conditions around a sample material can then be used as boundary conditions when modeling TPS material response. Two separate combustion models with equilibrium chemistry were investigated using ANSYS Fluent™; the Eddy-Dissipation Model, and the Partially Premixed model.The results of this study are compared to existing experiments for validation.

Stratospheric Glider Measurements Of Atmospheric Parameters, Anisa Haghighi

Theses and Dissertations--Mechanical and Aerospace Engineering

In June 2021 a series of high altitude flights were conducted in Spaceport America, NM, using a balloon launched Uncrewed Aircraft System (UAS) to assess its capability to conduct measurements of various atmospheric properties and study turbulence in the troposphere and lower stratosphere. This UAS descends using an automated flight trajectory. The instruments aboard included a NASA-developed infrasonic microphone to evaluate its remote turbulence detection capabilities and a five-hole probe capable of measuring the in situ wind vector. Also on board were temperature, humidity and wind profile sensors. This document focuses on the atmospheric properties measured at high altitudes, the …

Impact Of Spallation And Internal Radiation On Fibrous Ablative Materials, Raghava Sai Chaitanya Davuluri

Theses and Dissertations--Mechanical and Aerospace Engineering

Space vehicles are equipped with Thermal Protection Systems (TPS) that encounter high heat rates and protect the payload while entering a planetary atmosphere. For most missions that interest NASA, ablative materials are used as TPS. These materials undergo several mass and energy transfer mechanisms to absorb intense heat. The size and construction of the TPS are based on the composition of the planetary atmosphere and the impact of various ablative mechanisms on the flow field and the material. Therefore, it is essential to quantify the rates of different ablative phenomena to model TPS accurately. In this work, the impact of …

Precision Meteorological Prediction Employing A Data-Driven, Adaptive, Real-Time (Dart) Approach, Sujit Sinha

Theses and Dissertations--Mechanical and Aerospace Engineering

The objective of this research is to improve precision meteorological prediction, benefiting both uncrewed aerial vehicle (UAV) operations by avoiding hazardous flight conditions and tracking contaminant or toxic clouds caused by incidents, accidents, or fires. The operational concept is to collect meteorological observations from instruments mounted on a swarm of UAVs, telemeter the data to a weather simulation model, revise the predicted solution by adapting the flow field to the observations, and then transmit the updated forecast to appropriate personnel as well as to the guidance system of UAVs for repositioning to the next set of most beneficial measurements. While …

Detonability Of A Rotating Detonation Combustor Seeded With Carbon/Hydrocarbon Particles At Fringe Operating Conditions, Matthew Hopwood

Electronic Theses and Dissertations, 2020-2023

The Rotating Detonation Combustor (RDC) has, in recent years, been a subject of great interest in the pressure-gain combustion research community. Researchers have been investigating the RDC as a potential improvement over current combustors in today's turbomachinery-based power generation systems. With the theoretical efficiency boost that detonations provide over deflagrating combustors, RDCs have the promise to be a next step in fuel/cost savings in the power generation industry. One mode of research to push an RDCs capabilities is the potential use of combustible carbon/hydrocarbon solid particles in addition to liquid or gaseous fuels. These particles are a source of high …

On The Simulation Of Supersonic Flame Holder Cavities With Openfoam, Zachary Chapman

Electronic Theses and Dissertations

One of the next major advancements in the aerospace industry will be hypersonic flight. However, to achieve hypersonic flight, propulsion systems capable of reaching hypersonic speeds need to be developed. One of the more promising hypersonic propulsion systems is the scramjet engine, however, several problems still need to be explored before reliable scramjet engines can be produced, the biggest being keeping the engine ignited. This has led to the use of flame holder cavities to create a region of subsonic flow within the engine to allow combustion to occur. High experimental costs make the use of computational fluid dynamic (CFD) …

Robust State Estimation Methods For Robotics Applications, Shounak Das

Graduate Theses, Dissertations, and Problem Reports (ETD)

State estimation is an integral component of any autonomous robotic system. Finding the correct position, velocity, and orientation of an agent in its environment enables it to do other tasks like mapping and interacting with the environment, and collaborating with other agents. State estimation is achieved by using data obtained from multiple sensors and fusing them in a probabilistic framework. These include inertial data from Inertial Measurement Unit (IMU), images from camera, range data from lidars, and positioning data from Global Navigation Satellite Systems (GNSS) receivers. The main challenge faced in sensor-based state estimation is the presence of noisy, erroneous, …

Design And Validation Of An Aerodynamic System For A Formula Sae® Vehicle Using Vehicle Dynamic Simulation And Experimentation, Evan S. Cole

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents the design, simulation, and experimental validation for the aerodynamic system for a Formula SAE® vehicle. The Society of Automotive Engineers ® (SAE) hosts a collegiate competition annually called Formula SAE® where students design, fabricate, and test a small “formula style” vehicle. The vehicle performs in relatively slow maneuvers, around different courses and tests to evaluate the vehicle’s overall performance. Over the years, collegiate teams have put significant research into the design and manufacturing of the aerodynamics of these vehicles. In order to justify this undertaking for future teams at West Virginia University’s Formula SAE® program, a comprehensive …

Study Of Nanocomposite Materials Using Molecular Dynamics, Prashik Sunil Gaikwad

Dissertations, Master's Theses and Master's Reports

There is an increase in demand for new lightweight structural materials in the aerospace industry for more efficient and affordable human space travel. Polymer matrix composites (PMCs) with reinforcement material as carbon nanotubes (CNTs) have shown exceptional increase in the mechanical properties. Flattened carbon nanotubes (flCNTs) are a primary component of many carbon nanotube (CNT) yarn and sheet materials, which are promising reinforcements for the next generation of ultra-strong composites for aerospace applications. These flCNT/polymer materials are subjected to extreme pressure and temperature during curing process. Therefore there is a need to investigate the evolution of properties during the curing …

Molecular Dynamics Modeling Of Polymers For Aerospace Composites, Swapnil Sambhaji Bamane

Dissertations, Master's Theses and Master's Reports

Polymer matrix composite materials are widely used as structural materials in aerospace and aeronautical vehicles. Resin/reinforcement wetting and the effect of polymerization on the thermo-mechanical properties of the resin are key parameters in the manufacturing of aerospace composite materials. Determining the contact angle between combinations of liquid resin and reinforcement surfaces is a common method for quantifying wettability. It is challenging to determine contact angle values experimentally of high-performance resins on CNT materials such as CNT, graphene, bundles or yarns, and BNNT surfaces. It is also experimentally difficult to determine the effect of polymerization reaction on material properties of a …

Nusat I Project, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A PowerPoint Presentation created by Professor Bob Twiggs titled "NUSAT I Project" from 2023.

Bifurcation Levels Of The Integral Manifolds Of The Newtonian N-Body Problem, Hannah G. Havel

CURE Proceedings

The N-body problem, first proposed by Isaac Newton, is a field of study in mathematics and physics that involves predicting the motion of particles moving under their mutual gravitational attraction. It has significance to many areas of science, including physics and computer science, and is crucial in understanding how the universe works. In fact, it was a primary motivation for Newton's development of calculus. An important application of the N-body problem is within celestial mechanics and involves how planets and other celestial bodies move with mutual gravitational attraction. It is important in developing how satellites behave in space using complicated …

Experimental Study For Improving The Productivity Of Laser Foil Printing, Tunay Turk, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This Study Aims to Improve the Productivity of Laser Foil Printing (LFP), Which is a Foil-Based Metal Additive Manufacturing (AM) Process. LFP Uses a Dual-Laser System to Fabricate a 3-Dimensional Part in a Layered Fashion by Performing Four Steps in Each Layer: Spot Welding, Pattern Welding, Contour Cutting, and Edge Polishing, All of Which Performed by Use of Lasers. We Experimentally Examined the Welding and Polishing Steps in This Study to Enhance LFP Productivity. the Jump Speed, Dwelling Duration, and Weld Path of Spot Welding and the Line Welding Speed and Wait Time between Weld Lines of Pattern Welding Are …

Ads-B Communication Interference In Air Traffic Management, George Ray

International Journal of Aviation, Aeronautics, and Aerospace

Automated Dependent Surveillance Broadcast (ADS-B) provides position and state information about aircraft and is becoming an essential component in the global air traffic management system. ADS-B transponders broadcast this key information on a common frequency to both other aircraft and to secondary surveillance radar systems located at ground stations. Both the aircraft transponders and the ground stations work together to assist in managing the commercial airspace. Since the aircraft transponders all broadcast on the same frequency and are in close proximity there is an apparent risk of interference and the garbling of the communications needed to manage the airspace.

The …

Statistical Analysis To Evaluate The Impact Of Quality Control And Quality Assurance On The Aircraft Maintenance Turnaround Time, Deepak Chandra Chandola, Seema Verma, Kamal Jaiswal, Rajendrra Prasad Khaolliya, Preeti Chandola

International Journal of Aviation, Aeronautics, and Aerospace

The turnover time for aircraft maintenance is crucial for the operational efficiency and profitability of airlines. Quality assurance (QA) and quality control (QC) procedures play a role in assuring the safe and reliable operation of aircraft. The purpose of this paper is to evaluate the impact of QC and QA on turnover time and to propose strategies for achieving a balance between quality and efficiency. A large-scale survey of airline and aviation maintenance organization maintenance staff was combined with a literature study to form a mixed-methods strategy. The findings indicate that quality control and quality assurance have a substantial impact …

Enhancing Trajectory-Based Operations For Uavs Through Hexagonal Grid Indexing: A Step Towards 4d Integration Of Utm And Atm, Deepudev Sahadevan Neelakandan, Hannah Al Ali

International Journal of Aviation, Aeronautics, and Aerospace

Aviation is expected to face a surge in the number of manned aircraft and drones in the coming years, making it necessary to integrate Unmanned Aircraft System Traffic Management (UTM) into Air Traffic Management (ATM) to ensure safe and efficient operations. This research proposes a novel hexagonal grid-based 4D trajectory representation framework for unmanned aerial vehicle (UAV) traffic management that overcomes the limitations of existing square/cubic trajectory representation methods. The proposed model employs a hierarchical indexing structure using hexagonal cells, enabling efficient ground based strategic conflict detection and conflict free 4D trajectory planning. Additionally, the use of Hexagonal Discrete Global …

Future Directions Of Space Education, Kimberly T. Luthi Dr., Andy Aldrin, Keith Wilson, Jim P. Solti

International Journal of Aviation, Aeronautics, and Aerospace

The future of space operations graduate education is reliant on industry leaders’ contributions to help forecast the needs of the industry. The aim of the current study is to build consensus on the future direction of the space industry and generate new knowledge on what the industry expects to occur in the future of space studies education. This study documents the responses of 14 industry experts who currently or previously held highly visible senior leadership positions in a company or organization within the government or the commercial space industry and have extensive experience in a variety of management and leadership …

Integrated Immunity-Based Methodology For Uav Monitoring And Control, Ryan G. Mclaughlin

Graduate Theses, Dissertations, and Problem Reports (ETD)

A general integrated and comprehensive health management framework based on the artificial immune system (AIS) paradigm is formulated and an automated system is developed and tested through simulation for the detection, identification, evaluation, and accommodation (DIEA) of abnormal conditions (ACs) on an unmanned aerial vehicle (UAV). The proposed methodology involves the establishment of a body of data to represent the function of the vehicle under nominal conditions, called the self, and differentiating this operation from that of the vehicle under an abnormal condition, referred to as the non-self. Data collected from simulations of the selected UAV autonomously flying a set …

Missile Modeling And Simulation Of Nominal And Abnormal Scenarios Resulting From External Damage, James Manuel Floyd Iii

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents the development of a six-degree-of-freedom flight simulation environment for missiles and the application thereof to investigate the flight performance of missiles when exposed to external damage. The simulation environment was designed to provide a realistic representation of missile flight dynamics including aerodynamic effects, flight control systems, and self-guidance. The simulation environment was designed to be modular, expandable, and include realistic models of external damage to the missile body obtained by adversarial counteraction.

The primary objective of this research was to examine missile flight performance when subjected to unspecified external damage, including changes in trajectory, stability, and controllability, …

Optimal Path Planning For Aerial Robots Using Genetic Algorithm, Anna Puigvert I Juan

Graduate Theses, Dissertations, and Problem Reports (ETD)

This thesis presents a path optimization solution for a robot in two different constrained 3-dimensional (3D) environments. The robot is required to travel from its current position to a goal position following minimum cost paths (optimal paths). The first environment has 3D obstacles that interfere with the robot’s path. The path cost for this environment accounts for the minimum distance traveled by the robot from the start to the goal position while avoiding obstacles. The second environment is the atmosphere of Venus, specifically a flyable region of this atmosphere with characteristics similar to Earth’s. This environment has strong westward winds …