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Articles 391 - 420 of 11097
Full-Text Articles in Aerospace Engineering
Space Degradable Pyrotechnic Fastener, Jonathan Baker
Space Degradable Pyrotechnic Fastener, Jonathan Baker
Honors Theses
Space debris has become a critical threat to orbital operations, with over 30,000 tracked objects currently circling Earth. Traditional separation charges used in satellite launches contribute significantly to this problem by generating unpredictable shrapnel that can remain in orbit for decades or centuries. This project proposes the design and development of a spacedegradable explosive bolt that exploits the harsh space environment to accelerate material breakdown after use.
The design utilizes advanced polymer materials selected for their susceptibility to degradation from UV radiation — an environmental factor abundant in Low Earth Orbit (LEO). Our prototype will be engineered to meet industry-standard …
Development Of A Liquid Propellant Rocket Engine With Integrated Water-Based Cooling Jacket, Mauricio Bautista, Jesus Cortes, Christian Lopez, Hugo Robles, Will Owens, Josh Sutton, Jayden Pace, Shelby Enlow
Development Of A Liquid Propellant Rocket Engine With Integrated Water-Based Cooling Jacket, Mauricio Bautista, Jesus Cortes, Christian Lopez, Hugo Robles, Will Owens, Josh Sutton, Jayden Pace, Shelby Enlow
Create@State
This projects describes the development of a liquid rocket engine with a metal casted cooling jacket. We test the system and provide simulation data for the project.
Development Of The Automated Verification And Validation System For The Improvement Of Operations Of Morehead State University's Dss-17, Austin S. Music
Development Of The Automated Verification And Validation System For The Improvement Of Operations Of Morehead State University's Dss-17, Austin S. Music
Morehead State Theses and Dissertations
A thesis presented to the faculty of the College of Science and Engineering Morehead State University in partial fulfillment of the requirements for the degree of Master of Science by Austin S. Music on April 16, 2026.
Three Degree Of Freedom Wave Energy Converter Design For Resonant Motion, Greg Ballen, David G. Wilson, Rush Robinett, Shangyan Zou, Wayne Weaver
Three Degree Of Freedom Wave Energy Converter Design For Resonant Motion, Greg Ballen, David G. Wilson, Rush Robinett, Shangyan Zou, Wayne Weaver
Michigan Tech Publications
As multiple-degree-of-freedom (3-DOF) wave energy converters (WECs) have demonstrated the ability to produce more power than single-degree-of-freedom devices, the challenge of designing buoys for efficient energy harvesting has increased in complexity. In this paper, a cylindrical WEC is designed to naturally resonate in surge, pitch, and heave modes at a specific target frequency of 0.2 Hz. By utilizing a penalty-based optimization method to balance buoyancy requirements with natural resonance, the design achieves minimal control force input, thereby reducing fluctuations in energy output and local energy storage requirements. The performance is evaluated under irregular sea states using a Bretschneider spectrum. Results …
Hypersonic Impact Method For Aerodynamics And Convective Heating (Hi-Mach) With Sensitivities, Jeremiah Goates, Logan Freeman, Nathan Hoch, Douglas Hunsaker
Hypersonic Impact Method For Aerodynamics And Convective Heating (Hi-Mach) With Sensitivities, Jeremiah Goates, Logan Freeman, Nathan Hoch, Douglas Hunsaker
Mechanical and Aerospace Engineering Student Publications and Presentations
The purpose of this paper is to present the development of an engineering level code for calculating hypersonic aerodynamics and convective heating, HI-Mach. Novel to this paper are the use of analytic methods for streamline tracing and the direct differentiation of geometric sensitivities for both forces and heat load. Independent panel inclination methods calculate the pressure distribution on the surface of a hypersonic vehicle. Normal shock relations provide the thermodynamic state on each panel. Streamlines are integrated using closed-form streamline equations. Flat plate formulas corrected for compressibility calculate the skin friction coefficient and acreage heat flux on each panel. Formulas …
Further Development Of A Low-Energy Arc-Ignition System For Nytrox/Abs Hybrid Propulsion Systems, Stephen A. Whitmore, Jared S. Coen, Ryan J. Thibaudeau
Further Development Of A Low-Energy Arc-Ignition System For Nytrox/Abs Hybrid Propulsion Systems, Stephen A. Whitmore, Jared S. Coen, Ryan J. Thibaudeau
Mechanical and Aerospace Engineering Faculty Publications
Utah State University has developed a high-performance “green” hybrid propulsion technology based on the unique electrical breakdown properties of 3D-printed acrylonitrile butadiene styrene. Using 3D-printed ABS as fuel, typical startup sequences require approximately 5–15 joules and, once started, the system can be sequentially fired with no additional energy inputs required. The number of possible ignitions is limited only by the amount of fuel. The most technologically mature version uses gaseous oxygen (GOX) as oxidizer and 3D-printed ABS as fuel. While GOX is mass-efficient, it lacks volumetric efficiency unless highly pressurized. Nytrox, a blend of GOX and nitrous oxide, improves propellant …
Impact Of Compositing Method Choice On Spectral Fidelity In Semi-Arid Mining Landscapes, Ruslan Nailevich Khadzhaev, Dilbarkhon Shamuradovna Fazilova
Impact Of Compositing Method Choice On Spectral Fidelity In Semi-Arid Mining Landscapes, Ruslan Nailevich Khadzhaev, Dilbarkhon Shamuradovna Fazilova
Technical science and innovation
This study examines the choice of satellite image compositing method for Landsat 8/9 (Collection 2 Level-2) imagery to calculate the Normalised Difference Vegetation Index (NDVI). This paper compares the methods used to create median and medoid composites for the Angren open pit coal mine. The 'synthetic' nature of the composites is quantified based on a spectral consistency metric. This involves assessing the equivalence of median and medoid values, and analysing the sensitivity of NDVI to the compositing method across varying surface types. A strongly right-skewed distribution of surface reflectance values was found, covering 82.8% of the pixels, mostly in areas …
Mathematical Modelling And Optimisation Of The Reactor For The Esterification Process Of Safflower Oil With N-Butyl Alcohol, Sadritdin Makhamatdinovich Turabdjanov Academician, Hasan Sadriddin Ugli Fozilov, Ozoda Bakhronovna Axmedova, Sadriddin Fayzullayevich Fozilov
Mathematical Modelling And Optimisation Of The Reactor For The Esterification Process Of Safflower Oil With N-Butyl Alcohol, Sadritdin Makhamatdinovich Turabdjanov Academician, Hasan Sadriddin Ugli Fozilov, Ozoda Bakhronovna Axmedova, Sadriddin Fayzullayevich Fozilov
Technical science and innovation
This study addresses the mathematical modelling and optimisation of a reactor for the esterification of safflower oil with n-butyl alcohol. To improve process controllability and reduce the need for numerous pilot-scale trials, an ideal-mixing continuous stirred-tank reactor (CSTR) model was adopted. Incorporating reaction kinetics, the effect of contact time on the relative viscosity of the product mixture was analysed. The modelling results indicate that achieving an acceptable degree of feedstock conversion is difficult when a single ideal-mixing reactor is used. Therefore, a CSTR cascade was proposed, and the configuration with N = 2 reactors was selected as the most appropriate …
Development Of New Methods For Calculating Pressure And Energy Losses For Pumping Station Water Intakes, Faxriddin Jaylovovich Nosirov, Oleg Yakovlevich Glovatsky, Jurabek Abdyrahmon O'G'Li Urolov, Abduqodirkhon Samatkhonovich Abdullakhaev, Anvar Mamur Ugli Uzokov
Development Of New Methods For Calculating Pressure And Energy Losses For Pumping Station Water Intakes, Faxriddin Jaylovovich Nosirov, Oleg Yakovlevich Glovatsky, Jurabek Abdyrahmon O'G'Li Urolov, Abduqodirkhon Samatkhonovich Abdullakhaev, Anvar Mamur Ugli Uzokov
Technical science and innovation
The aim of this study is to improve the efficiency of water resource management methods. Improvements to the water intake of the Karshi Main Canal are considered using calculations of pressure losses at the entry and exit of liquid into the flow, which differ from pressure losses in a stationary medium. The article considers some of the methods for using renewable energy sources, where the change in gravitational potential energy does not depend on the way of using energy and the operating scheme is a gravitational energy pump. The implementation of control and monitoring systems is necessary to ensure optimal …
Refinement Of Wind Speed Estimation At Turbine Hub Height Using Satellite Data And Regression Analysis Under Complex Terrain Conditions, Isroil Abriyevich Yuldoshev, Tulqin Rustamovich Jamolov, Sa'dullo Sayfiddin Ugli Fazliddinov, Jumanazar Farhodjon OʻGʻL Abdurashidov
Refinement Of Wind Speed Estimation At Turbine Hub Height Using Satellite Data And Regression Analysis Under Complex Terrain Conditions, Isroil Abriyevich Yuldoshev, Tulqin Rustamovich Jamolov, Sa'dullo Sayfiddin Ugli Fazliddinov, Jumanazar Farhodjon OʻGʻL Abdurashidov
Technical science and innovation
Reliable assessment of wind energy potential in regions characterized by complex terrain is often constrained by the limited availability of ground-based meteorological measurements. This study proposes an improved regression-based approach for refining wind speed estimates at the wind turbine hub height of 65 m using satellite-derived data from the NASA POWER database combined with a logarithmic vertical wind profile. The proposed methodology is validated using real operational data from a 750 kW wind power plant located in the mountainous Bostanlyk district of Uzbekistan for the period 2018–2021. The regression analysis demonstrates a strong linear relationship between the extrapolated wind speed …
Theoretical And Practical Foundations Of Healthcare System Digitalization, Sanjarbek Bekturdiev Sharifboyevich Phd, Muxlisa G‘Ulom Qizi G‘Ofurova
Theoretical And Practical Foundations Of Healthcare System Digitalization, Sanjarbek Bekturdiev Sharifboyevich Phd, Muxlisa G‘Ulom Qizi G‘Ofurova
Technical science and innovation
The digital transformation of healthcare represents a key direction in improving the accessibility, quality, and efficiency of medical services. This study examines the main components of eHealth, including telemedicine, electronic health records, cloud technologies, and mobile applications, as well as the role of international organizations in promoting national digital health strategies. Particular attention is given to the current state of digital healthcare in the Republic of Uzbekistan, where significant progress has been made in developing infrastructure and implementing information systems, although challenges related to integration, standardization, and regulatory support remain. The work identifies the main trends in the development of …
Manufacturing Of Functional Surface Coatings In The Automotive Industry, Gulirano Saidakhmedova
Manufacturing Of Functional Surface Coatings In The Automotive Industry, Gulirano Saidakhmedova
Technical science and innovation
The development of environmentally sustainable technologies for material processing represents one of the most pressing scientific and technical challenges in modern industrial production. This issue is particularly relevant to the automotive industry, where growing demands for energy efficiency, durability, and environmental safety necessitate the adoption of advanced manufacturing methods. Special attention is given to developing vacuum-based, import-substituting equipment and technologies for producing functional coatings from composite materials with predefined physical, mechanical, and optical properties, including reflective and protective characteristics. Current requirements for mechanical engineering products and production technologies drive the need for innovative approaches to material processing and specialized technical …
Biomass Demineralization: A Critical Need For Future Biorefineries, Leoncio Santiago-Martínez, Styliani Avraamidou, Alejandro Ayala-Cortés, Ruth Azike, Santanu Bakshi, Chumki Banik, Ezra Bar Ziv, Fei Long, Rebecca Ong, Et Al.
Biomass Demineralization: A Critical Need For Future Biorefineries, Leoncio Santiago-Martínez, Styliani Avraamidou, Alejandro Ayala-Cortés, Ruth Azike, Santanu Bakshi, Chumki Banik, Ezra Bar Ziv, Fei Long, Rebecca Ong, Et Al.
Michigan Tech Publications
Biomass contains up to 14 essential elements that serve as nutrients for plant growth and development, including photosynthesis and enzyme functionalities. These elements in different chemical forms (e.g., minerals) constitute the inorganic fraction of biomass and can cause operational issues in thermal and biochemical biomass conversion technologies. In biomass gasification and pyrolysis processes, for instance, inorganics can cause fouling, tar formation, and corrosion. In catalytic and biochemical processes, inorganics can poison catalysts, alter biochemical pathways, and modify product yields and selectivity. This review provides an overview of the inorganic content in biomass feedstocks, the critical role inorganics play in plant …
A Platform For Acquiring And Classifying Low-Noise Electrocardiogram Signals For Applications In Cardiovascular Monitoring, Begmamat Berdimurodovich Dushanov, Narzullo Mamatov Dr.
A Platform For Acquiring And Classifying Low-Noise Electrocardiogram Signals For Applications In Cardiovascular Monitoring, Begmamat Berdimurodovich Dushanov, Narzullo Mamatov Dr.
Technical science and innovation
The early screening and continuous monitoring of cardiovascular diseases need effective acquisition and smart processing of electrocardiogram (ECG) signals. In this article, we introduce a compact platform designed for the acquisition of low-noise ECG signals and classification of the signals using a one-dimensional convolutional neural network (1D-CNN). Our compact platform consists of a low-noise analog front-end (AFE), including an instrumentation amplifier and a chain of analog filters, along with a data acquisition component designed to ensure effective suppression of baseline wander and high frequencies. Our compact platform consumes a low amount of power and can therefore be used for continuous …
Thermoacoustic Effects Of A Variable Equivalence Ratio In A Single Element Methane Combustor, Carter Green
Thermoacoustic Effects Of A Variable Equivalence Ratio In A Single Element Methane Combustor, Carter Green
Doctoral Dissertations and Master's Theses
Combustion instability is one of the leading factors in limiting the progress and innovations of liquid rocket engines and power plants. Under certain operating conditions, unsteady heat release and acoustic wave interactions can couple and lead to instabilities, such as self-sustaining pressure oscillations, that can lead to reduced combustor performance and potentially hardware damage. In this project, the thermoacoustic effects of controlling the equivalence ratio of a single-element natural gas combustor were modeled and analyzed. The project used Fidelity Pointwise for meshing, ANSYS Fluent for modeling, ERAU VEGA HPC for computing, and MATLAB for acoustic analysis. A numerical model of …
Simulating Thermal Diffusion Through Image-Derived Microstructures Of Ceramic Matrix Composites, Matik Heskin
Simulating Thermal Diffusion Through Image-Derived Microstructures Of Ceramic Matrix Composites, Matik Heskin
Miners Solving for Tomorrow Research Conference
Thermal energy transport in materials can be effectively modeled using finite element software such as COMSOL. Experimentally measured or NIST–JANAF thermal conductivity data can be used to represent material behavior within these simulations. For heterogeneous or composite materials, effective properties are often approximated using rule-of-mixtures calculations. However, this overlooks the nuanced effects caused by complex microstructural geometry. To address this limitation, imaging and coding tools such as MATLAB can be used to process scanning electron microscopy (SEM) images. By thresholding the images to distinguish constituent materials, a representative mesh can be generated and imported into an FEM program. This approach …
Designing Space-Based Architectures To Discover And Track Hazardous Asteroids Using Mo-Mcts, Adam P. Wilmer, Michael J. Klonowski, Marcus J. Holzinger, Robert A. Bettinger
Designing Space-Based Architectures To Discover And Track Hazardous Asteroids Using Mo-Mcts, Adam P. Wilmer, Michael J. Klonowski, Marcus J. Holzinger, Robert A. Bettinger
Faculty Publications
The discovery and tracking of near-Earth objects (NEOs), such as asteroids and comets, form the foundation of any effective planetary defense mitigation strategy—that is, the process of reducing or eliminating the threat these objects pose to humanity. Establishing sufficient warning time prior to a potential Earth impact is a critical outcome of this capability, as it enables informed decision-making and the selection of viable mitigation options. This study investigates how to optimally pre-position a fleet of NEO discovery and tracking (D&T) spacecraft within the Sun-Earth system. Candidate architectures—one or more pre-positioned spacecraft—are designed using Multi-Objective Monte Carlo Tree Search (MO-MCTS). …
Cooperative Unmanned Aerial System (Uas) Geolocation Of Emitters, Christopher Peters
Cooperative Unmanned Aerial System (Uas) Geolocation Of Emitters, Christopher Peters
Electrical Engineering Theses and Dissertations
A collection of unmanned aerial systems (UAS) can be networked as a cooperative wireless sensor array to geolocate an unknown-location RF emitter using time-based measurements. In operation, however, environmental multipath and hardware errors in sensor positioning and timing can degrade emitter localization accuracy and limit the practicality of single-snapshot solutions. This dissertation evaluates time-of-arrival and time-difference-of-arrival (TOA/TDOA) geolocation for cooperative UAS arrays under realistic error sources and develops geometry-control strategies that actively reduce localization uncertainty through iterative UAS repositioning.
This work studies the Location on a Conic Axis (LOCA) method for emitter localization. Using Monte Carlo simulations with hardware error …
Numerical Study Of Nutrient Mixing In Trabecular Bone In Microgravity, Disuse And Normogravity, Sagar Gharti
Numerical Study Of Nutrient Mixing In Trabecular Bone In Microgravity, Disuse And Normogravity, Sagar Gharti
Doctoral Dissertations and Master's Theses
Mechanical loading is known to regulate bone remodeling by driving interstitial fluid flow which stimulates cells and drives nutrient transport within the trabecular network. In microgravity, the absence of mechanical stimulation or loading suppresses convective flow processes, causing diffusion-driven nutrient mixing and renewal, and accelerated bone loss. This thesis investigates how oscillation frequency and trabecular bone density jointly control nutrient mixing and wall shear stress within trabecular cavities.
A computational fluid dynamics (CFD) framework is developed in STAR-CCM+ using a soft-cap oscillation model that mimics cyclic compression. Three idealized trabecular morphologies are simulated across different frequencies to represent microgravity or …
Instrumentation And Control Of A Novel Device To Simulate A Hypersonic Environment, Andrew Marcello
Instrumentation And Control Of A Novel Device To Simulate A Hypersonic Environment, Andrew Marcello
Doctoral Dissertations and Master's Theses
The hypersonic flow regime poses several challenges regarding the design of hypersonic vehicles. Among them is the massive energy and economic expense associated with ground- testing evaluation of material responses within this extreme environment. In order to provide a low-cost, rapid option for preliminary material analysis within hypersonic applications, a novel device is under production to replicate this environment on the surface of these materials. This device has been designed to work in conjunction with Argonne National Laboratory (ANL) Advanced Photo Source (APS) synchrotron, to allow for in-situ characterization of ablation and oxidation on the sample surface.
To achieve this, …
Numerical Investigation Of Rotor-Gust Acoustic Interactions Using The Overflow Cfd Solver, Jordan Mills
Numerical Investigation Of Rotor-Gust Acoustic Interactions Using The Overflow Cfd Solver, Jordan Mills
Doctoral Dissertations and Master's Theses
The rapid expansion of Urban Air Mobility (UAM) necessitates high-fidelity modeling to predict and mitigate the noise signatures of electric vertical take-off and landing (eVTOL) aircraft within dense urban landscapes. A critical unknown in community-noise certification is the aeroacoustic response of rotors to unsteady inflow conditions. This research addresses this gap by investigating the aerodynamic and acoustic behavior of a representative rotor subjected to time-harmonic inflow disturbances. By establishing a robust numerical framework, this thesis quantifies the relationship between periodic atmospheric gusts and their impact on rotor performance, unsteady blade loading, and subsequent sound radiation. The research consists of a …
Effect Of Nozzle Pressure Ratio On Thrust And Flow Behavior In A Supersonic De Laval Nozzle, Esha Jain
Effect Of Nozzle Pressure Ratio On Thrust And Flow Behavior In A Supersonic De Laval Nozzle, Esha Jain
Doctoral Dissertations and Master's Theses
Supersonic nozzles operate across a range of flow regimes. While an ideally expanded condition yields optimal thrust, practical propulsion systems rarely operate at this design point due to variations in altitude and engine operating conditions. As a result, nozzles frequently operate in off-design conditions. In overexpanded regime, where the exit pressure is lower than the ambient pressure, shock-induced separation may occur within the divergent section of the nozzle, potentially degrading nozzle performance. Understanding the aerodynamic behavior of nozzles operating under off-design conditions is therefore important for improving propulsion system performance and stability. In particular, direct thrust measurements provide a key …
Intelligent Flight Control Systems Using Adaptive Deep Neural Networks And Concurrent Learning-Based Design Methods, Maddox C. Morrison
Intelligent Flight Control Systems Using Adaptive Deep Neural Networks And Concurrent Learning-Based Design Methods, Maddox C. Morrison
Doctoral Dissertations and Master's Theses
This thesis investigates deep neural network (DNN)-based adaptive control strategies for unmanned aerial vehicles (UAVs) operating under aerodynamic uncertainty and complex actuator dynamics.
The first contribution presents a control strategy employing a concurrent learning (CL)-based DNN training algorithm, which combines online adaptive DNN weight adaptation with offline batch-like training updates using a recorded data stack. The analysis focuses on the closed-loop performance improvements resulting from the use of optimum CL data-selection algorithms, which ensure that the recorded data stack maintains sufficient data diversity to provide a statistically meaningful representation of the operating conditions using a reduced data set. Specifically, this …
Safety-Aware Trajectory Generation For Increased Autonomy In Advanced Air Mobility, Edison Alberto Martinez Samaniego
Safety-Aware Trajectory Generation For Increased Autonomy In Advanced Air Mobility, Edison Alberto Martinez Samaniego
Doctoral Dissertations and Master's Theses
Advanced Air Mobility (AAM) envisions highly automated aircraft that will enable short and medium range transportation. Unlike conventional aviation, these vehicles are expected to operate closer to populated areas and with increased levels of autonomy, making safe operation under abnormal or degraded conditions a critical requirement. Failures or performance degradation can reduce the maneuvering capability of an aircraft, causing trajectories planned under nominal conditions to become dynamically unfeasible.
This thesis presents a trajectory generation and replanning framework designed to maintain safe and feasible flight under reduced flight envelope conditions for a lift+cruise eVTOL aircraft. A unified control architecture based on …
Quantification Of The Depth-Of-Field In A Self-Aligned Focusing Schlieren System, Alexander Ephraim
Quantification Of The Depth-Of-Field In A Self-Aligned Focusing Schlieren System, Alexander Ephraim
Doctoral Dissertations and Master's Theses
This thesis investigates self-aligned focusing schlieren (SAFS) as a step toward future volumetric and quantitative measurements of three-dimensional compressible flows. Conventional schlieren imaging provides valuable visualization of density gradients, but it records only a line-of-sight projection and therefore does not directly resolve the spatial distribution of structures through the depth of the flowfield. SAFS addresses part of this limitation by introducing depth sensitivity, but its depth response has not been well characterized quantitatively. To help lay the foundation for future volumetric and quantitative SAFS methods, this work addresses two related problems. First, calibrated quantitative schlieren imaging is applied to an …
Adaptive Methods Of Resident Space Object Identification For Space Situational Awareness, Evan Pavetto-Stewart
Adaptive Methods Of Resident Space Object Identification For Space Situational Awareness, Evan Pavetto-Stewart
Doctoral Dissertations and Master's Theses
One of the fundamental tenets of Space Situational Awareness (SSA) is the detection and sub sequent identification of Resident Space Objects (RSOs) within unresolved optical space imagery. This function is vital to the documentation and tracking of RSOs in their respective operational orbits, knowledge that is necessary for collision avoidance efforts and Space Domain Awareness (SDA) applications. In previous work, development was begun on a MATLAB program called RSOID to fulfill this purpose by accepting a collection (or ’collect’) of unresolved imagery and outputting a sequence of RSO locations (called a ’tracklet’) that can be used to determine the RSO’s …
Evaluating Uav Visual-Inertial Odometry Trajectory Error And Feature-Level Metrics Over Repetitive Floor Patterns, Anass El Mekkoussi
Evaluating Uav Visual-Inertial Odometry Trajectory Error And Feature-Level Metrics Over Repetitive Floor Patterns, Anass El Mekkoussi
Doctoral Dissertations and Master's Theses
Visual-Inertial Odometry (VIO) is a widely used state estimation technique for Uncrewed Aerial Vehicle (UAV) navigation in environments where Global Navigation Satellite System (GNSS) signals are unavailable. VIO systems that rely on visual feature tracking are susceptible to performance degradation when operating over surfaces containing repetitive visual textures, where visually similar features can produce ambiguous correspondences that introduce errors into the trajectory estimate. Despite the prevalence of repetitive textures in indoor UAV operating environments such as warehouses, manufacturing facilities, and infrastructure corridors, the specific impact of different repetitive pattern geometries on per-surface VIO accuracy has received limited systematic study, and …
Artificial Intelligence In Human Spaceflight Safety-Critical Systems: A Requirements Framework For Ai-Enabled Computer-Based Control Systems, Liz Bosch
Doctoral Dissertations and Master's Theses
Currently, there is no governing standard that addresses the safe integration of AI into computer-based control systems (CBCS) in human spaceflight. The computer-based control expectations of those safety-critical systems on the International Space Station (ISS) are captured in SSP 50038, Computer-Based Control System Safety Requirements, with one caveat: the standard was not designed with AI applications in mind. SSP 50038 does not cover the probabilistic behavior, opacity, and training-data dependency of modern AI/ML systems. The objectives of this work is to develop an AI taxonomy relevant to safety characteristics (determinism, transparency, data dependency, failure predictability), systematically map AI characteristics against …
Modeling And Autonomous Control Systems For A Delivery Drone Application, Dana Helal Alnuaimi
Modeling And Autonomous Control Systems For A Delivery Drone Application, Dana Helal Alnuaimi
Theses
This thesis focuses on the development of a multi-drone navigation and control system, aiming to enhance payload capacities beyond the limits of single-drone systems. By integrating multiple drones to work collaboratively as a unit, this study addresses the challenges associated with lifting and transporting heavier payloads.
The primary objective is to design and evaluate a multi-drone system capable of working in tandem to transport larger payloads efficiently. The research aims to develop robust control algorithms, supported by system identification for dynamic modeling, and navigation strategies to enable effective coordination between drones.
The study employs a combination of simulation and real-world …
Enhancing Nasa Sounding Rocket Capabilities Through Composite Material Adoption, Robert Burth
Enhancing Nasa Sounding Rocket Capabilities Through Composite Material Adoption, Robert Burth
Mechanical & Aerospace Engineering Theses & Dissertations
Sounding rockets are a suborbital research platform employed by NASA for heliophysics, astrophysics, geospace science investigations, and for technology development. They follow semi-parabolic trajectories and are launched using surplus military, and commercial, solid-propellant rocket motors. NASA sounding rocket payloads are comprised of standard, modular subassemblies, designed to perform specific functions critical to achieving specific mission success criteria.
Since the program’s inception, payload length and mass have trended upwards, limiting the capability of the platform to reach exospheric apogees and decreasing the time above critical altitudes to observe solar and celestial targets. To offset this trend, composite materials may be of …