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Articles 841 - 870 of 11113
Full-Text Articles in Engineering
Data-Driven D Region Model (D3r) Svdd: Software Version Description Document (Svdd), James Vincent Eccles
Data-Driven D Region Model (D3r) Svdd: Software Version Description Document (Svdd), James Vincent Eccles
Space Dynamics Laboratory Publications
This is the Software Version Description Document of the Data-Driven D Region (D3R) model. There are 2 main distributions: (a) D3R designed for containerized deployments (D3Rc) and (b) D3R designed for testing and development. These two distributions are maintained in parallel, and this document describes both. The D3R for containerization is typically provided to customers. The D3R model is a physics-based model for calculating electron density profiles across the D Region ionosphere altitudes (50 km to 95 km) and E Region altitudes (95 km to 120 km) for any given geolocation. The model has two main programs: one to solve …
Utilizing Augmented Reality For Immersive Space Mission Design, Joseph Anderson
Utilizing Augmented Reality For Immersive Space Mission Design, Joseph Anderson
Doctoral Dissertations and Master's Theses
Designing spacecraft mission trajectories is a complex, tedious, and stringent process that requires a strong background in astrodynamics and programming due to the complex dynamical environment of space. The current 2D visualization methods for displaying these geometrically abstract trajectories make it difficult to understand the true nature of more complex orbits. Advancements in immersive headsets and their intuitive interaction capabilities make them ideal for solving and understanding 3D problems that require complex spatial representations, revealing an innovative and unique opportunity for the astrodynamics and space mission planning field. This effort covers the development of an immersive space mission design tool …
Boeing 747 Fixed Drive Link Redesign, Eric White
Boeing 747 Fixed Drive Link Redesign, Eric White
Honors Theses
This project focuses on redesigning the fixed drive link for the Boeing 747-400, a critical component of the flap actuation system that connects the drive mechanism to the flaps. Over recent years, this part has been prone to fracturing under full flap deflection. The Federal Aviation Administration (FAA) and Boeing have investigated this issue but have not successfully developed a durable solution.
This problem was presented by Kalitta Air, an air freight company experiencing frequent failures and costly maintenance related to the fixed drive link. If fracturing of the fixed drive link occurs the component must immediately be replaced. Similar …
Flow Characterization Past Large Arrays Of Oscillating 2d Airfoils, Yi-Cheng Chen
Flow Characterization Past Large Arrays Of Oscillating 2d Airfoils, Yi-Cheng Chen
Student Research Symposium
Oscillating or rotating array structures at distinct frequencies are prevalent in natural systems and engineering applications.
• Flow Control in Engineering Systems:
Arrays of vibrating plates can be used to manipulate free-shear and boundary layer flows, reduce drag, or delay flow separation in aerodynamics and hydrodynamics.
• Wave Mitigation Structures:
Arrays of oscillating structures may dissipate energy in coastal areas, reducing the impact of waves on structures or preventing erosion
• Biological Studies:
Simulations of synchronized oscillating arrays can provide insights into fish schooling behavior and hydrodynamic benefits in nature.
• Advanced Cooling Systems:
Oscillating plates in fluid environments …
Production And Decay Of Sheared Turbulence In A Turbulence Box, Ankit Gautam
Production And Decay Of Sheared Turbulence In A Turbulence Box, Ankit Gautam
Student Research Symposium
Introduction
- Turbulence
- Irregular flow with eddies, swirls, and flow instabilities
Simulating Low Gravity Particle Dynamics, Ryan Lewis
Simulating Low Gravity Particle Dynamics, Ryan Lewis
Student Research Symposium
- Vibrating motors prevent particle arches from forming and clogging nozzle.
- A metal mesh under the nozzle creates an evenly dispersed stream.
- Nozzle is static dissipative to ensure particles have consistent path through the charging section.
A Pressure-Based Estimate Of Multi-Orifice Synthetic Jet Performance, Rhett Parry
A Pressure-Based Estimate Of Multi-Orifice Synthetic Jet Performance, Rhett Parry
Student Research Symposium
Synthetic Jets
- Zero-Net Mass Flux
- Wide voltage and frequency response
- Trends with physical and nondimensional parameters
A Model Predictive Control To Improve Grid Resilience, Joseph Young, David G. Wilson, Wayne Weaver, Rush Robinett
A Model Predictive Control To Improve Grid Resilience, Joseph Young, David G. Wilson, Wayne Weaver, Rush Robinett
Michigan Tech Publications
The following article details a model predictive control (MPC) to improve grid resilience when faced with variable generation resources. This topic is of significant interest to utility power systems where distributed intermittent energy sources will increase significantly and be relied on for electric grid ancillary services. Previous work on MPCs has focused on narrowly targeted control applications such as improving electric vehicle (EV) charging infrastructure or reducing the cost of integrating Energy Storage Systems (ESSs) into the grid. In contrast, this article develops a comprehensive treatment of the construction of an MPC tailored to electric grids and then applies it …
40 - Design, Fabrication, And Installation Of Morphing Control Surfaces For Small-Scale Uas, Kyle Purser
40 - Design, Fabrication, And Installation Of Morphing Control Surfaces For Small-Scale Uas, Kyle Purser
Undergraduate Research Symposium
Morphing control surface technology, inspired by organic structures and compliant mechanisms, offers significant potential for enhancing the aerodynamic efficiency and performance of unmanned aerial systems (UAS). Despite these benefits, its adoption has been hindered by complexities in design, manufacturing, and installation, particularly when compared to traditional flap systems. This research explores the design, fabrication, and integration of morphing control surfaces for small-scale UAS using additive manufacturing techniques. To reduce costs and streamline the design process, fused deposition modeling (FDM) additive manufacturing was employed for component fabrication. An off-the-shelf Horizon Sport Cub S2 served as the testing platform, modified with a …
Wind-Resilient Solar: Harnessing Cfd For Enhanced Load Estimation, Aly Mousaad Aly
Wind-Resilient Solar: Harnessing Cfd For Enhanced Load Estimation, Aly Mousaad Aly
Faculty Publications
Solar panels are a cornerstone of renewable energy infrastructure, playing a pivotal role in global sustainability efforts. To ensure their resilience and long-term viability, accurate wind load estimations are essential for designing supporting structures, which account for nearly 50% of their total cost. However, traditional building codes lack comprehensive guidance for solar panels, resulting in inconsistent estimations due to discrepancies in scaled wall-bounded wind tunnel testing methodologies. These inaccuracies pose safety risks, increase costs, and hinder adoption. Emerging technologies like computational fluid dynamics (CFD) simulations offer a promising alternative by enabling full-scale analysis under realistic conditions of complete turbulence. This …
Fabrication Of Ultra High-Temperature Compact Heat Exchanger By Extrusion-Based Ceramic Additive Manufacturing, Abid Hasan Rafi, David W. Lipke, Jeremy Lee Watts, Greg Hilmas, Ming-Chuan Leu
Fabrication Of Ultra High-Temperature Compact Heat Exchanger By Extrusion-Based Ceramic Additive Manufacturing, Abid Hasan Rafi, David W. Lipke, Jeremy Lee Watts, Greg Hilmas, Ming-Chuan Leu
Miners Solving for Tomorrow Research Conference
No abstract provided.
Multidisciplinary Design Optimization Of A Notional Cubesat Mission, Collin Gentry
Multidisciplinary Design Optimization Of A Notional Cubesat Mission, Collin Gentry
Miners Solving for Tomorrow Research Conference
No abstract provided.
Image-Based Stage Prediction Of Pressure Injuries Using Deep Learning, Mehedi Tusar, Fateme Fayyazbakhsh, Ming-Chuan Leu
Image-Based Stage Prediction Of Pressure Injuries Using Deep Learning, Mehedi Tusar, Fateme Fayyazbakhsh, Ming-Chuan Leu
Miners Solving for Tomorrow Research Conference
No abstract provided.
Additive Manufacturing Of Thermoplastic Composites, Matik Heskin, K. Chandrashekhara, Richard Billo, Ming-Chuan Leu, Thomas P. Schuman
Additive Manufacturing Of Thermoplastic Composites, Matik Heskin, K. Chandrashekhara, Richard Billo, Ming-Chuan Leu, Thomas P. Schuman
Miners Solving for Tomorrow Research Conference
No abstract provided.
Design Of A Two-Point Focused Laser Differential Interferometry System For The Missouri S&T Supersonicwind Tunnel, Joseph Villarreal, Davide Vigano
Design Of A Two-Point Focused Laser Differential Interferometry System For The Missouri S&T Supersonicwind Tunnel, Joseph Villarreal, Davide Vigano
Miners Solving for Tomorrow Research Conference
No abstract provided.
Design Of A High Performance, Affordable, Liquid Bi-Propellant Sounding Rocket Leveraging Additive Manufacturing And A Novel Injector Design, Nick Graham
Miners Solving for Tomorrow Research Conference
No abstract provided.
Quantifying Shock Effects On Small Drone Components, Parker Barnes, Avery Lyons, Phillip R. Mulligan
Quantifying Shock Effects On Small Drone Components, Parker Barnes, Avery Lyons, Phillip R. Mulligan
Miners Solving for Tomorrow Research Conference
No abstract provided.
L2 Certification Rocket Launch, Seungyou Cho
L2 Certification Rocket Launch, Seungyou Cho
SACAD: Scholarly Activities
The LOC 835 high-power rocket with J275W-12 motor at Argonia, KS, for L2 certification, was auspiciously launched and returned. J means the motor can exert 640-1280 Ns of impulse, which makes a sizeable propelling sound. Even though four main hindrances occurred from the construction to the launch, the issues were revised correctly. The rail button and the tracker were severe issues, so I devised the method of drilling a hole for the rail button, but there was no way to replace a broken tracker. The wind speed on the launch day was so strong that the rocket flew 1-2 miles …
Exploring Strategies And Innovations In Airline Profitability Assessment: The Role Of Artificial Intelligence, Elif Degirmenci
Exploring Strategies And Innovations In Airline Profitability Assessment: The Role Of Artificial Intelligence, Elif Degirmenci
Journal of Global Hospitality and Tourism
The airline industry's profitability assessment remains a complex yet critical aspect of strategic decision-making, spanning from hub profitability to individual flight performance. This paper explores the diverse methodologies and challenges involved in evaluating both line and network profitability, emphasizing the need for innovative approaches in reconciling variable costs associated with aircraft types and route assignments. Traditional methods are juxtaposed with innovative concepts like the Blended Aircraft Cost model, offering insights into enhancing market route profitability. Additionally, advanced methodologies such as horizontal and vertical methods are discussed, alongside the role of artificial intelligence in revolutionizing real-time profitability analysis. Through a comprehensive …
Emission Behavior At The Single Emitter Scale From A Porous Media Ionic Liquid Ion Source, Thomas Victor Kerber
Emission Behavior At The Single Emitter Scale From A Porous Media Ionic Liquid Ion Source, Thomas Victor Kerber
Dissertations
Ionic liquid ion sources (ILIS) are being developed as one solution to fill a technology gap in low power, high efficiency, high specific impulse space propulsion systems. With a sufficiently intense electric field applied between an emitter electrode and an extractor electrode, charged particles are extracted from the fluid surface and accelerated out of the thruster. In this work, three experimental campaigns examine emission behavior of a single emitter ILIS made of porous material that allows passive propellant feed via capillary action of the ionic liquid 1-ethyl-3-methylimidazolium tetrafluoroborate (EMI-BF4).
Repeated measurements of the emitter and extractor current as …
Turbulence And Energetic Ion Production In The Partially Magnetized Hollow Cathode Plume, Margaret Mary Mooney
Turbulence And Energetic Ion Production In The Partially Magnetized Hollow Cathode Plume, Margaret Mary Mooney
Dissertations
Hall effect thrusters (HETs) are the most widely used electric propulsion (EP) device for in-space satellite propulsion. EP devices provide high efficiencies for extended mission lifetimes and low thrust for precision maneuvers. The hollow cathode is a critical HET component and undergoes extensive lifetime testing in addition to the lifetime testing of the full HET. Significant density gradients, non-Maxwellian electron behavior, and magnetic fields sufficiently strong enough to magnetize electrons in hollow cathode plumes create favorable conditions for the formation of plasma instabilities, which have an impact on cathode lifetime. Cathode qualification testing is typically conducted independently and includes a …
Multiphase Iterative Algorithm For Mixed-Integer Optimal Control, Chaoying Pei, Sixiong You, Yu Di, Ran Dai
Multiphase Iterative Algorithm For Mixed-Integer Optimal Control, Chaoying Pei, Sixiong You, Yu Di, Ran Dai
Mechanical and Aerospace Engineering Faculty Research & Creative Works
Mixed-integer optimal control problems (MIOCPs) frequently arise in the domain of optimal control problems (OCPs) when decisions including integer variables are involved. However, existing state-of-the-art approaches for solving MIOCPs are often plagued by drawbacks such as high computational costs, low precision, and compromised optimality. In this study, we propose a novel multiphase scheme coupled with an iterative second-order cone programming (SOCP) algorithm to efficiently and effectively address these challenges in MIOCPs. In the first phase, we relax the discrete decision constraints and account for the terminal state constraints and certain path constraints by introducing them as penalty terms in the …
Towards Universal Non-Dimensional Characterization Of The Oscillatory Dynamics Of Wind Turbine Rotors Of Multiple Sizes, North Yates, Fernando L. Ponta, Alayna Farrell
Towards Universal Non-Dimensional Characterization Of The Oscillatory Dynamics Of Wind Turbine Rotors Of Multiple Sizes, North Yates, Fernando L. Ponta, Alayna Farrell
Michigan Tech Publications
One concern in the field of Horizontal Axis Wind Turbines (HAWTs) is what control strategies are needed to handle gust pulses in the wind to prevent extreme oscillations of the blades to reduce fatigue stress, prevent blade rupture, and extend the turbine’s operational life. In order to design innovative control strategies to modify the blade’s oscillatory response, it is crucial to establish the fundamental vibrational behavior of the blades when excited by gust pulses of different frequencies and amplitudes present in the fluctuating wind inflow. In a series of previous works, the authors presented a novel Reduced-Order Characterization (ROC) technique …
Adaptive Control Of Thrusters To Account For Deficiencies In Actuator Effectiveness And Model Uncertainties, Matthew Stanko
Adaptive Control Of Thrusters To Account For Deficiencies In Actuator Effectiveness And Model Uncertainties, Matthew Stanko
Doctoral Dissertations and Master's Theses
Future space missions are expected to become ever more ambitious and challenging. A successful mission requires advanced and resilient control algorithms that enable missions, such as satellite refueling, on-orbit inspection, and end-of-life servicing. This thesis explores the development and application of robust and adaptive control laws for an over-actuated spacecraft system with 3 degrees of freedom (DoF) to mitigate the effects of actuator deficiencies and system uncertainties. Additionally, the nature of the system being over-actuated allows for particular actuator degradation and failure. For stability and command tracking, a novel controller is designed and augmented with sliding mode control, adaptive control, …
Engineering Anisotropic Porosity In Green Parts From Binder Jet 3d Printing, Reshma Chandrashekhar Kubsad
Engineering Anisotropic Porosity In Green Parts From Binder Jet 3d Printing, Reshma Chandrashekhar Kubsad
Doctoral Dissertations and Master's Theses
Binder Jet Additive Manufacturing (BJAM) is a promising metal additive manufacturing technique that enables the fabrication of complex geometries without the need for support structures. However, the inherent porosity in green parts, remains a challenge in achieving desired mechanical properties and performance. Instead of treating porosity as a limitation, this thesis explores engineering of anisotropic porosity engineering, where controlled variations in porosity in the green parts can be used to enhance functionality and efficiency in specific applications. The objective of this research is to investigate and analyze the key print parameters that influence green part density. By systematically varying layer …
The Interaction Of A Transient Forward Axial Disturbance Flow With A Rotor, Zhuorui Li
The Interaction Of A Transient Forward Axial Disturbance Flow With A Rotor, Zhuorui Li
Doctoral Dissertations and Master's Theses
This research presents an in-depth investigation of the aeroacoustic characteristics of a scaled-down Joby Aviation rotor, focusing on its performance under realistic conditions for urban air mobility (UAM). Utilizing a high-fidelity numerical simulation approach that combines Large-Eddy Simulation (LES) and Unsteady Reynolds-Averaged Navier-Stokes (URANS) models, the study effectively captures the complex aerodynamic and acoustic interactions inherent in rotor operations. Validation of the numerical framework was achieved through comprehensive comparisons with available experimental data, demonstrating a high level of accuracy in predicting both aerodynamic performance metrics, including thrust and torque, as well as acoustic emissions. The simulation revealed significant impacts resulting …
Aeroacoustics Applications To Jets And Rotors, Michael Marques G.
Aeroacoustics Applications To Jets And Rotors, Michael Marques G.
Doctoral Dissertations and Master's Theses
Aeroacoustics plays a critical role in the advancement of propulsion technologies for both conventional and emerging aerial systems. This dissertation investigates two key topics: noise suppression in supersonic rectangular jets and rotor noise characterization in hover and ground effect. Using high-fidelity numerical simulations and theoretical analyses, this research aims to develop effective noise mitigation strategies and improve predictive methodologies.
The first part of this study focuses on the reduction of noise in supersonic rectangular jets through active control techniques. A novel approach utilizing unsteady microjet actuation at the nozzle lip is explored to disrupt the formation of large-scale turbulent structures …
Coupled Dynamics In The Cislunar Region And Spacecraft Attitude Prediction In A Higher-Fidelity Model, Annika Anderson
Coupled Dynamics In The Cislunar Region And Spacecraft Attitude Prediction In A Higher-Fidelity Model, Annika Anderson
Doctoral Dissertations and Master's Theses
The cislunar region of space is a complex, multi-body dynamical environment that cannot be modeled trivially. Traditional point-mass assumptions made to simplify the mission design process may be insufficient for accurately predicting spacecraft motion in environments where orbit-attitude coupling is non-negligible. One of the most famous of such models is the circular restricted three-body problem. This thesis advances the state of the art in astrodynamics by modeling all bodies in the problem as rigid bodies, allowing for spacecraft orientation to be propagated and considered. Two models are under consideration—the circular restricted full three-body problem (CRF3BP) and a full higher-fidelity ephemeris …
Machine Learning Methods For Hypervelocity Fragment Flyout Characterization, Katharine Larsen
Machine Learning Methods For Hypervelocity Fragment Flyout Characterization, Katharine Larsen
Doctoral Dissertations and Master's Theses
Resulting from breakup events, such as collisions and explosions, hypervelocity fragments create potential hazards for both terrestrial and on-orbit environments, such as terrestrial weapons explosions and satellite breakup events, respectively. To avoid unnecessary damage, an accurate understanding or characterization of hypervelocity fragmentation events is vital. Currently, publicly available two-line elements collected from on-orbit breakup events are limited, excluding pre-detonation parent body conditions, such as orientation, and information of smaller fragments. The uncertainty of these datasets varies between each collected set. Therefore, the overall goal of this work is to employ machine learning to estimate distribution characteristics of a space debris …
Stability Limits Of Uncertain Systems In The Presence Of Unmatched Coupled Dynamics And Actuator Dynamics With Adaptive Architectures, Bronson Saulo
Stability Limits Of Uncertain Systems In The Presence Of Unmatched Coupled Dynamics And Actuator Dynamics With Adaptive Architectures, Bronson Saulo
Doctoral Dissertations and Master's Theses
Uncertain systems with coupled dynamics and actuator dynamics are prevalent in various applications spanning private, commercial, and government sectors. While stabilization and command tracking strategies exist, they often rely on idealized assumptions, such as negligible actuator bandwidth limitations and matched coupled dynamics. In order to mitigate actuator-induced limitations, we first employ standard model reference adaptive control (MRAC) architectures. We then proposed two architectures: modified hedging reference modeled based MRAC and modified expanded reference model based MRAC. In order to deal with coupled dynamics, we used an observer design to estimate the states of unmatched coupled dynamics. In addition, Lyapunov stability …