Aerospace Engineering Commons^™

Adaptive Control For Spacecraft With Flexible Appendages With Unknown Parameters, Nicolo Woodward

Doctoral Dissertations and Master's Theses

Flexible spacecraft pose several challenges in control design due to the uncertain dynamical model and the underactuated nature of these systems. Adaptive and robust controllers are the common choice for these systems to either meet operational requirements like attitude pointing or to suppress vibrations. However, these controllers add complexity in the design of onboard Attitude Determination and Control Systems (ADCS) and the Reaction Control Systems (RCS) for spacecraft maneuvering. The objective of this research is to control a system that undergoes unpredictable and unknown disturbances through onboard derivation of an equivalent reduced order model designed around mounted sensors. The proposed …

Dissociation Of Subjective And Objective Measures Of Trust In Vehicle Automation: A Driving Simulator Study, Samuel Petkac, Tetsuya Sato, Kun Xie, Yusuke Yamani

Psychology Faculty Publications

Trust is a crucial factor that influences human-automation interaction in surface transportation. Previous research indicates that participants tend to display higher levels of subjective trust toward lower-level automated systems compared to high-level automated systems. However, administering subjective trust measures via questionnaires can interfere with primary task performance, limiting researchers' ability to measure trust continuously in a real-world manner. In the current driving simulator study, 25 drivers using an advanced driving system (ADS) were randomly assigned to either an active (L2) or passive (L3) automated driving condition. Participants experienced eight near-miss driving scenarios with or without obstructions in a distributed driving …

Extraction Of Aluminum From Lunar Regolith Through Molten Salt Electrolysis, Jacob N. Ortega, Todd P. Sander, Jeffrey D. Smith, Fateme Rezaei, David J. Bayless, William Schonberg, Daniel S. Stutts, Frank D. Han

Materials Science and Engineering Faculty Research & Creative Works

This paper presents the methodology, development, and results of an end-to-end regolith-to-metal concept for producing aluminum in-situ on the lunar surface, namely, the Lunar In-Situ Aluminum Production through Molten Salt Electrolysis (LISAP-MSE) method. Using electrolytic reduction, aluminum oxide (i.e., alumina) can be reduced into aluminum and oxygen via electrolysis in a molten salt bath. A steady supply of hydrogen chloride could allow this in-situ resource utilization (ISRU) method to supply several necessary materials consumed in the electrolytic reduction step of the process to produce bulk aluminum metal, oxygen, water, and silica from anorthite abundant in lunar highland regions. In this …

Jet Impingement And Vortex/Swirl Cooling Of Different Inlet And Outlet Geometrical Configurations For Turbine Blade Leading Edge Cooling, Irfan Ahmad Sheikh

Dissertations

Gas turbine blades operate in extreme environments, exposed directly to high-temperature combustion gases that cause severe thermal stresses, weaken material integrity, and may lead to structural failure. Proper cooling is crucial to lower blade temperatures, reduce thermal stresses, prevent failure, and improve overall engine efficiency. This work presents a detailed numerical study of various cooling configurations by applying two advanced leading-edge cooling methods, jet impingement and swirl cooling, across different inlet mass flow rates and jet Reynolds numbers (Rej) ranging from 1,000 to 20,000 to evaluate their cooling performance.

Several advanced leading-edge cooling configurations are proposed and compared with the …

System Characterization Of A Distributed Pressure Sensor Array, Bryan C. Hasselman

Master's Theses

This thesis contributes to ongoing research on bluff body aerodynamics at California Polytechnic State University, San Luis Obispo, by introducing a novel technique for the dynamic characterization of a commercially available digital MEMS pressure sensor. The experimental approach combines a new characterization method with comparisons to traditional techniques, offering a comprehensive evaluation of the sensor’s dynamic performance. Both non-parametric and parametric system identification methods are employed to assess the sensor’s frequency response. This thesis supports further investigations into unsteady aerodynamic forces and provides a cost-effective, hands-on platform for students to gain practical experience with instrumentation, system identification, and frequency-domain analysis.

Downwind-Upwind Flux Path Analysis Method For Model Reduction Performance Evaluations, Christian Robert Smith

Theses and Dissertations

Large, complex chemical kinetic models have long since been limited by the computational cost it takes to evaluate said model. Over time many reduction methods have been developed to combat this computational cost. However, very little has been done towards evaluating the limitations of reductions as a way of understanding the original model’s characteristics. This paper aimed to use a path flux analysis-based reduction algorithm to rapidly develop multiple reduced mechanisms for a 96 species FFCM-2 methane chemical kinetic model as well as an 858 species n-Dodecane chemical kinetic model. The goal of formulating these reduced mechanisms was to identify …

A Building Block Approach To Certification By Analysis Applied To A Ditching Analysis, Preliminary Studies, Sean Taylor

Theses and Dissertations

Extended Twin-Engine Operations (ETOPS) certification ensures safe trans-oceanic operation of transport category aircraft. A critical aspect of ETOPS certification is compliance with ditching regulations. The importance of ditching analysis has grown significantly and come under greater scrutiny because of the ‘Miracle on the Hudson’ incident. For transport category aircraft certified under 14 CFR 25 regulations, compliance with ditching requirements, rests on two major components. First, demonstrating acceptable aircraft dynamic behavior during the ditching event and second, ensuring the airframe can withstand the loads generated because of water impact.

Historically, original equipment manufacturers (OEMs) relied on comparisons to existing aircraft with …

Calculating Surface Current Velocities From Video Generated From A Near Forward-Facing Camera, Colby James Weeks

Theses and Dissertations

This work presents a camera system for estimating surface currents. A combined camera and IMU system provide high resolution images and high precision orientation information, respectively. This eliminates the need for leveling and enables forward looking operation. The hardware stack includes a Lucid Vision Triton TRT162S monochrome camera, an SBG Ellipse D with dual antenna GNSS for precise pose, and an Nvidia Jetson Orin for acquisition and processing. The Ellipse D provides a hardware trigger at 10 Hz to time stamp each frame and to synchronize images with inertial measurements.

A camera calibration step estimates the intrinsic camera parameters and …

Feasibility Of Helium And Nitrogen As Surrogate Gases For Hydrogen Jet Using Planar Laser-Induced Fluorescence In A Constant Volume Chamber, Jungho Justin Kim, Seong Young Lee, Youngmin Ki, Joonsik Hwang, Choongsik Bae

Michigan Tech Publications

This study investigates the feasibility of using helium and nitrogen as surrogate gases for visualizing the non-reactive behavior of hydrogen jets in a constant volume chamber. Hydrogen, helium, and nitrogen were individually mixed with acetone vapor and injected using a hollow-cone injector. The fuel distribution was visualized using Planar Laser-Induced Fluorescence (PLIF), while simultaneous Schlieren imaging was employed to capture overall jet structures. Quantitative comparisons of jet areas extracted from both imaging techniques demonstrated that acetone effectively followed the gas-phase flow of each species, validating its use as a flow tracer. Furthermore, helium and nitrogen exhibited jet dispersion patterns comparable …

Warpage-Resistant, Under-Extrusion-Free, High-Surface-Quality Additive Manufacturing Process For Polyethylene-Based Composite Radiation Shielding Material, Duo Xu, Volodymyr Korolovych, You Lyu, Jacqueline Aslarus, Domingo R. Flores-Hernandez, Simo Pajovic, William T. Heller, Lembit Sihver, Svetlana V. Boriskina

Informatics and Engineering Systems Faculty Publications

Polyethylene (PE) is one of the best shielding materials for primary space radiation due to its high hydrogen content. For effective secondary neutron shielding, boron-rich fillers are incorporated to enhance performance. The semicrystalline nature and high thermal expansion coefficient of PE impede its adoption for in situ additive manufacture in space via the fused deposition modeling (FDM) 3D printing. We developed an optimized PE blend to mitigate the effects of under-extrusion and warpage. Guided by studies on extrusion and warpage, we developed an optimal set of printing parameters for the proposed PE blend. The optimum PE blend─both in its pure …

Enhancing High Cycle Fatigue Perfomance Of Electron Beam Melted Ti6al4v: A Study On Shot Peening And Hot Isostatic Pressing, Naghmeh M. Mojib, Dwayne D. Arola, Ramulu Mamidala

15th International Conference on Shot Peening

The qualification of electron beam powder bed fusion (PBF-EB) for safety-critical applications is hindered by variability in high cycle fatigue performance, largely due to surface roughness and internal defects. While Hot Isostatic Pressing (HIP) effectively reduces internal porosity, it does not address surface-initiated fatigue failures. This study investigated the combined effects of HIP and shot peening on enhancing the fatigue performance of PBF-EB Ti6Al4V. Over 50 specimens, including both vertical and horizontal build orientations, underwent high cycle fatigue testing per ASTM E466. X-Ray computed tomography confirmed decrease in defect distribution following HIP, while shot peening resulted in a more uniform …

Improvement Of The Fatigue Behaviour Of Additive Manufatured Scalmalloy By Using Surface Improvement Processes, Francisco José Boby Alcaide, Irene Eras, José Manuel De Los Santos, Alejandro Munoz Castro, Antonio Perinan Butrón, Jorge Sogorb

15th International Conference on Shot Peening

The use of light metals such as Aluminum alloys has experienced a remarkable increase for the additive manufacturing (AM) industry, especially in aerospace.

AM Scalmalloy®. (an Al-Mg-Sc alloy) shows outstanding behavior with much higher mechanical performance with respect to other alloys for powder bed fusion laser-based (PBF-LB) process like AlSi10Mg or AlSi7Mg. Recent studies have mainly focused on static loading, with minor attention to cyclic loading despite its vital importance in many applications.

In this work, the fatigue performance of PBF-LB Scalmalloy was investigated considering the effects of surface treatments to identify the set of optimal post-processes. Shot peening with …

Methodologies And Applications Of Precision Shot Peening To Hole Or Slot Geometry, James C. Hoffman

15th International Conference on Shot Peening

Shot peening, a commonly used method of fatigue and surface enhancement, is a critical process in many of the components in the aerospace industry. When it comes to small holes and/or slot geometries in these components, the process can become a challenge when these features are smaller than a conventional size Almen strip. In these cases, a decision must be made about how to process this type of geometry. Oftentimes, the method to apply the shot peen process is already defined in a process specification or part print so we must adhere to that method. If a method is not …

The E-Strip® As A Tool For Predictive Maintenance To Monitor And Control Shot Peening Processes, Walter A. Beach, Scott Glasier

15th International Conference on Shot Peening

The primary objective of this paper is to demonstrate the E-Strip® is capable of providing real-time feedback to the machine controller for making necessary process adjustments due to external forces, such as machine wear. Adjustments may include regulating air pressure and shot flow within pre-defined tolerances dictated by specification. It is anticipated that this integrated approach will significantly reduce variations in intensity levels observed from part to part and lot to lot.

Improving Fatigue Strength And Life Of Single Crystal Cmsx-4, Jochen Peter Fuhr, Lloyd Hackel, Nicolau I. Morar, Noah Holtham, Keivan Davami, Montu Sharma, Rajkumar Roy

15th International Conference on Shot Peening

The deep penetration of laser peening (LP) and retention of residual stress at high temperature by LP is significant in improving fatigue life and strength of superalloys exposed to high temperature and corrosion. Single crystal CMSX-4, was evaluated for stress relaxation and both fatigue life and fatigue strength of material that was LP-treated compared to non-LP and shot-peened (SP) specimens. LP was done with multiple layers using a 20 J/pulse laser where the laser high energy enabled using a 5 mm spot size on the metal surface. Stress measurements by the slitting technique showed the plastic penetration depth exceeded SP …

Overcoming Variable Illumination In Photovoltaic Snow Monitoring: A Real-Time Robust Drone-Based Deep Learning Approach, Amna Mazen, Ashraf Saleem, Kamyab Yazdipaz, Ana Dyreson

Michigan Tech Publications

Snow accumulation on photovoltaic (PV) panels can cause significant energy losses in cold climates. While drone-based monitoring offers a scalable solution, real-world challenges like varying illumination can hinder accurate snow detection. We previously developed a YOLO-based drone system for snow coverage detection using a Fixed Thresholding segmentation method to discriminate snow from the solar panel; however, it struggled in challenging lighting conditions. This work addresses those limitations by presenting a reliable drone-based system to accurately estimate the Snow Coverage Percentage (SCP) over PV panels. The system combines a lightweight YOLOv11n-seg deep learning model for panel detection with an adaptive image …

Performance Of A Two-Body Wave Energy Converter With An Annular Heave Plate, Raj Tamakuwala, Muhammad Usman, Nathan Tom, Hassan Masoud

Michigan Tech Publications

We theoretically examine the performance of a two-body wave energy converter (WEC) featuring a floating sphere and a submerged annular heave plate, connected by a power take-off (PTO) system. Utilising linear wave theory, we derive the system's frequency-domain response to regular plane waves and analyse the impact of varying disk porosity on power generation. Our results suggest that annular disks can enhance power extraction efficiency in various cases compared with solid heave plates. Additionally, permeable plates can broaden operational conditions by reducing oscillation amplitudes and decreasing the mechanical strain on the PTO system without substantially compromising the power conversion efficiency. …

Cryogenic Gas Cell For Infrared Space Instrumentation, Trent Newswander, Scott Bailey, Mark Hervig, Phillip Scott, Ryan Luder, Mike Watson, Mike Oksness, Cody Secrist, Zack Hatfield

Space Dynamics Laboratory Publications

The Doppler Wind and Temperature Sounder (DWTS) is being developed for flight on NASA’s Dynamical Neutral Atmosphere-Ionosphere Coupling (DYNAMIC) satellite. DWTS will view the Earth limb orthogonal to the spacecraft ram and uses gas-filter correlation radiometry to detect the Doppler shift of atmospheric emission. The observations yield horizontal winds and kinetic temperature with high precision, excellent spatial resolution, and altitude coverage from 40–250 km. DWTS detects Doppler shifting of NO and 13CO2 atmospheric emission lines by passing the incident light through an onboard cell containing both gases that is cooled to near cryogenic temperatures. This work describes the DWTS instrument, …

Occulation Observations With Event-Based Vision Sensors [ Poster ], Rachel Oliver, Paul Rickerhauser, Brian Mcreynolds

Faculty Publications

Event-based vision sensors (EVS) offer exceptional change detection capabilities due to their asynchronous and independent pixels which record binary events with changes in their photocurrent. The resulting address event representation data is a sparse timeseries list.

A Feasibility Study Into The Usability And Application Of An Unmanned Aerial Vehicle For Aircraft Inspection And Quality Assurance Inspections, Reece P. Bhave

Journal of Aviation Technology and Engineering

The global aviation industry is often characterized as one of the safest modes of transportation in the modern world. With an abundance of quality assurance inspections and checks to determine operations safety, modern-day commercial aircraft that are utilized for passenger and cargo flights are held to a higher safety standard defined by regulatory bodies, such as the Federal Aviation Administration in the United States of America and the European Union Aviation Safety Agency in the European Union. While these quality standards are maintained via a series of inspections, checks, and preventative maintenance procedures, they are limited to only visual or …

Self-Organization In Metal Plasticity: An Ilg Update †, Avraam Konstantinidis, Konstantinos Spiliotis, Amit Chattopadhyay, Elais C. Aifantis

Michigan Tech Publications

In a 1987 article of the last author dedicated to the memory of a pioneer of classical plasticity Aris Philips of Yale, the last author outlined three examples of self-organization during plastic deformation in metals: persistent slip bands (PSBs), shear bands (SBs) and Portevin Le Chatelier (PLC) bands. All three have been observed and analyzed experimentally for a long time, but there was no theory to capture their spatial characteristics and evolution in the process of deformation. By introducing the Laplacian of dislocation density and strain in the standard constitutive equations used for these phenomena, corresponding mathematical models and nonlinear …

Energy-Aware Optimal Reconfiguration Of A Heterogeneous Connected And Automated Vehicle Cohort On A Limited-Access Highway, Pruthwiraj Santhosh, Darrell Robinette, Daniel Knopp, Jeffrey Naber, Jungyun Bae

Michigan Tech Publications

This paper presents an optimized vehicular reordering methodology designed to minimize energy consumption within heterogeneous cohorts operating at constant velocity on limited-access highways. The approach addresses the challenge of optimizing vehicle sequencing by considering both aerodynamic drag reduction benefits and the energy costs of reconfiguring a cohort from a stochastic initial state. This study provides empirical validation through on-road vehicle tests, demonstrating significant energy savings, achieving up to 10% reduction in axle energy for optimally configured cohorts compared to independent operation. A System of Systems (SoS) simulation environment, integrating micro-traffic, validated powertrain, and aerodynamic drag reduction models, was developed to …

Terra Lunaris: Assessment Of A Lunar Habitat For Scientific Astronauts, Space Miners, Or Space Tourists, Dirk Schumann, Robert A. Goehlich

Publications

This conceptual paper explores ground- based habitable space modules for various applications. The Terra Lunaris concept serves as the baseline and is evaluated in comparison to existing and theoretical studies in this field. Terra Lunaris is a compact hybrid habitat that expands to offer nearly four times its transport volume by combining rigid modules with an inflatable shell. With most interior elements pre-installed and foldable, setup time and complexity are minimized. The design integrates technical zones, living quarters, and shared spaces, while also supporting psychological well-being under extreme conditions. The paper provides both qualitative and quantitative analyses of lunar habitation …

Nitric Oxide Radiometer Development, Deron Scott, Phil Scott, Trent Newswander, Marty Mlynczak

Space Dynamics Laboratory Publications

SDL developed a small satellite payload to support the NICEcube mission concept capable of measuring vertical profiles of infrared radiance at 5.3 µm from nitric oxide (NO) in the atmospheric limb (100-250 km). These radiance measurements can be directly inverted to achieve vertical profiles of infrared cooling rates which are crucial to understanding the density response to the thermosphere in times of elevated geomagnetic activity. The payload was designed to fit on a 12U cube sat, function at low power and small mechanical envelope. Completed work includes building the telescope, integrating a representative detector, alignment, test planning, and initial testing. …

A Polar Turbulence Invariant Map With Applicability To Realisable Machine Learning Turbulence Models, James G. Wnek, Christopher Schrock, Eric M. Wolf, Mitch Wolff

Mechanical and Materials Engineering Faculty Publications

Invariant maps are a useful tool for turbulence modelling, and the rapid growth of machine learning-based turbulence modelling research has led to renewed interest in them. They allow different turbulent states to be visualised in an interpretable manner and provide a mathematical framework to analyse or enforce realisability. Current invariant maps, however, are limited in machine learning models by the need for costly coordinate transformations and eigendecomposition at each point in the flow field. This paper introduces a new polar invariant map based on an angle that parametrises the relationship of the principal anisotropic stresses, and a scalar that describes …

A Test Rig For An Aircraft Propeller Powered By Battery Motor, C. M. Vigneswaran, J. Induja, K. S. Bharath, M. J. Spoorthi, R. Chethana

Journal of Aviation Technology and Engineering

The propeller test rig is a crucial component in aeronautical engineering that plays a vital role in the development, testing, and optimization of propeller systems for aircraft. This research outlines the design, development, and performance evaluation of a state-of- the- art propeller test rig developed for research and testing purposes. The primary objective of this project is to enhance the understanding of propeller dynamics and efficiency, leading to the improvement of aircraft propulsion systems. The test rig provides a controlled environment to evaluate and compare multiple propeller designs, aiding engineers in making informed decisions during the design process. An advanced …

A Framework For Test Planning Of A Vision System Supporting Aerial Refueling, Jonathon K. Parry, Donald H. Costello, Michael D. M. Kutzer, Charles J. Doherty, Sarah M. Hubbard

Journal of Aviation Technology and Engineering

This essay presents a framework for evaluating a computer vision system providing perception for an uncrewed aircraft completing the automated air-to-air refueling (A3R) task. As the Department of Defense acquires capabilities that exhibit increasing levels of autonomy, the test and evaluation community must adapt the current framework to provide airworthiness officials the information required to accurately access the risks associated with the system underdoing testing. Following a brief introduction to A3R, this essay lays out a testing framework that leverages dendritic analysis and effectively deconstructs the critical issue into measurable data elements that can be used to support test and …

Event-Based Sensor Noise Modeling For Space-Based Space Domain Awareness, Rachel Oliver, Brian Mcreynolds, Dmitry Savransky

Faculty Publications

Building off the foundation of a physics-based end-to-end model for event-based vision sensors (EVS) observing resident space objects (RSOs), we apply new techniques to model realistic low-light sensor noise. While previous approaches simulate memorized current leakage and apply temporal noise models, our methods improve on these approaches and additionally account for current-following noise as an event source. These improvements are key components for accurate event-generating simulators which can advise requirements and concepts of operations for dedicated event-based Space Domain Awareness (SDA) architectures. The EVS pixel’s independent and asynchronous recording of changes in photocurrent produces data with high temporal resolution and …

The Atmospheric Waves Experiment (Awe), L. Scherliess, M. J. Taylor, P.-Dominique Pautet, Y. Zhao, B. Lamborn, H. Latvakoski, G. Cantwell, P. Sevilla, E. Syrstad, J. Forbes, S. Eckermann, D. Fritts, D. Janches, H. Liu, J. Snively

Space Dynamics Laboratory Publications

Modern theory and modeling indicate that atmospheric gravity waves (AGWs) play an important role in vertical coupling of the atmosphere-ionosphere system. Although small-scale AGWs (horizontal wavelengths ~30–300 km) are thought to account for the dominant energy and momentum inputs at Ionosphere-Thermosphere-Mesosphere (ITM) altitudes, the sources, variability, and influences of small-scale AGWs are still major unknowns. NASA’s Atmospheric Waves Experiment (AWE) mission is a Heliophysics Small Explorers Mission of Opportunity designed to investigate how terrestrial weather affects space weather, via small-scale AGWs produced in Earth’s atmosphere. Installed on the International Space Station (ISS) in November 2023, AWE began its 2-year mission …

Distributed Coherent Beamforming At 60 Ghz Enabled By Optically-Established Coherence, Drake Silbernagel, Yu Rong, Isabella Lenz, Prithvi Hemanth, Carl Morgenstern, Owen Ma, Nolan Matthews, Nadar Zaki, Kyle W. Martin, John D. Elgin, Jacob Holtom, Daniel W. Bliss, Kimberly Frey

Space Dynamics Laboratory Publications

We implement and experimentally demonstrate a 60 GHz distributed system leveraging an optical time synchronization system that provides precise time and frequency alignment between independent elements of the distributed mesh. Utilizing such accurate coherence, we perform receive beamforming with interference rejection and transmit nulling. In these configurations, the system achieves a coherent gain over an incoherent network of N nodes, significantly improving the relevant signal power ratios. Our system demonstrates extended array phase coherence times, enabling advanced techniques. Results from over-the-air experiments demonstrate a 14.3 dB signal-to-interference-plus-noise improvement in interference-laden scenarios with a contributing 13.5 dB null towards interference in …