Aerospace Engineering Commons^™

Performance Trades For Multiantenna Gnss Multisensor Attitude Determination Systems, Nathan A. Tehrani, Jason N. Gross

Faculty & Staff Scholarship

We present various performance trades for multiantenna global navigation satellite system (GNSS) multisensor attitude estimation systems. In particular, attitude estimation performance sensitivity to various error sources and system configurations is assessed. This study is motivated by the need for system designers, scientists, and engineers of airborne astronomical and remote sensing platforms to better determine which system configuration is most suitable for their specific application. In order to assess performance trade-offs, the attitude estimation performance of various approaches is tested using a simulation that is based on a stratospheric balloon platform. For GNSS errors, attention is focused on multipath, receiver measurement …

Flow Control Of Tandem Cylinders Using Plasma Actuators, Jonah Larsen

Honors Undergraduate Theses

The flow over a set of tandem cylinders at a moderate Reynolds numbers (Re), and with different separation lengths has been studied. Two dimensional (2D) and three-dimensional (3D) plasma actuators were used to control the flow over the leading cylinder to change the vortex shedding, and subsequently the flow on the second cylinder. The 3D plasma actuator was segmented along the length of the cylinder with a spacing of λ = 4 while the 2D actuator simply ran straight down the span of the cylinder. Particle image velocimetry (PIV) measurements were used to investigate the flow along the central plane …

Specific Air Range (Sar) And How To Estimate It, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Affordable Small System Calibration & Tvac Testing, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Ensure that your sensor will perform correctly during operation by validating image quality, radiometric performance, and operation temperature performance!

The Space Dynamics Laboratory (SDL) has been calibrating electro-optical sensors for over 50 years. During this time, SDL has designed and developed a collection of specialized equipment that is available for calibrating smaller optical systems, which can be very affordable.

Optimal Maneuvers For Safe Rpo Using Relative Orbital Elements And Sequential Convex Programming, Nicholas G. Ortolano, David K. Geller, Aaron Avery

Space Dynamics Laboratory Publications

Passive safety of flight constraints for orbital rendezvous and proximity operations trajectory design are imposed as a means for ensuring zero probability of collision in the event of a passive failure on the chaser satellite. For a chaser satellite near a target satellite in a near circular reference orbit, relative orbital elements are used to develop safety of flight constraints. Using relative orbital elements, the problem is formulated as a minimum ∆v convex optimization problem in which the optimal transfer trajectories are guaranteed to not pass within a prescribed distance of the target satellite in the event of a …

Thermal Straps: High-Performance Thermal Management, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

Thermal straps efficiently transfer heat from a heat source to a temperature sink while minimizing the transfer of mechanical loads. SDL has been pioneering solderless flexible thermal straps (a.k.a. thermal links) since 1994.

Monolith: Spacecraft, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

SDL’s Pearl spacecraft architecture delivers the performance, reliability, and mission flexibility needed for demanding small satellite missions. The Pearl architecture draws from common sets of components to build 3U, 6U, 12U, and custom sizes with variations in mission capability, parts quality, and radiation tolerance. This flexibility enables our professional staff to develop systems specific to each mission while drawing on a common design to maintain reliability and costs.

Snpp Cris Noise Characterization And Relative Response After 5 Years In Space, Kori Moore, Mark Esplin, Deron Scott

Space Dynamics Laboratory Publications

CrIS Background

Satellite-based, infrared, Fourier transform spectrometer

• Provides Earth surface, atmospheric, and weather observations
• Global coverage twice daily

Launched and operational CrIS instruments

• Suomi National Polar-orbiting Partnership (SNPP) spacecraft, launched Oct. 2011, operational since Apr. 2012
• SNPP follow-on system (J1) launched Nov. 2017, expected operational spring 2018

A Performance Analysis Of On-Board Numerical Propagators, Simon Shuster, David Geller, Tyson Smith

Space Dynamics Laboratory Publications

On-board targeting, guidance, and navigation relies on orbit propagation algorithms that must strike a balance between accuracy and computational efficiency. To better understand this balance, the performance of numerical propagation methods is analyzed for LEO, GEO, and Molniya orbits. A numerical propagator consists of a set of differential equations describing perturbed orbital motion whose solution is approximated using a numerical integration method. This paper compares Cowell, Encke-time, Encke-beta, and Equinoctial Elements formulations over a range of integration function evaluations for a given set of perturbations and integrators. Function evaluations are shown to be a reasonable approximation of normalized computation time. …

Slanted-Edge Mtf Focus Test Verification With Prf Testing To Establish Best Focus Position Of Infinite Conjugate Space Optical Systems, Lennon Reinhart, Trent Newswander, Duane Miles, David W. Riesland, Deron Scott

Space Dynamics Laboratory Publications

For earth-viewing, fixed-focus, space optical systems, carefully finding the best focus position of the instrument is critical to achieving the best possible image performance and mission success. For such space optical systems, modulation transfer function (MTF) test data is directly applicable to system optical resolution. Furthermore, MTF test products can be combined to predict overall imaging performance. The infinite conjugate slanted-edge MTF test can be used in ground testing to identify best focus of the optical system while taking into account the entire imaging system, operational parameters, and simulated operational environment. The point-response function (PRF) test can be used to …

The Separation Of Shear-Driven Liquid Films From A Sharp Corner, Zahra Sadeghizadeh

Doctoral Dissertations

"The separation of shear-driven liquid films occurs in many engineering applications such as port fuel injected engines, demisters, and gas transfer lines. Despite the importance of this problem, the details of the interaction between operating parameters such as liquid flow rate, gas velocities and liquid film properties on the forces at the expanding corner are still not clear. To enhance the insight on the complicated interaction between the gas and liquid phases, the shear-driven liquid flow around a corner has been studied both experimentally and analytically in this work. The effect of the complex liquid film structure on liquid mass …

Characterization Of Acoustic Modes In Aeroengines, Michelle Otero

Electronic Theses and Dissertations

Acoustic instabilities remain a key design concern faced in the development of liquid rocket engines. The interaction between the acoustic modes and the occurring combustion reactions can be detrimental to the engine. The fluctuating pressure waves resulting from the flame oscillations in the system can potentially lead to engine failure. For this reason, research in acoustic instabilities and methods to minimize the influences on the engine, has maintain interest in the aerospace community. The scope of this study was to design, optimize and characterize acoustic behaviors of a scaled rocket combustion chamber simulating acoustic pressure waves. Tangential and longitudinal acoustic …

Neowise: Near Earth Object Wide-Field Infrared Survey Explorer, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

NEOWISE began as the Wide-field Survey Explorer (WISE), a highly sensitive astronomical telescope that surveyed the entire sky in four mid‐infrared bands spanning from 2.6 to 26 microns. Launched in December 2009, WISE scanned the entire sky one and a half times and cataloged hundreds of millions of astronomical objects, including many asteroids, brown dwarf stars, and ultra‐ luminous infrared galaxies.

Gr: Geospatial Reality, Space Dynamics Laboratory

Space Dynamics Laboratory Publications

The Space Dynamics Laboratory developed Geospatial Reality (GR), a Government-owned, open software architecture that enhances military/DoD system capability by visually presenting warfighters with tactically relevant, geospatial situational awareness information in real time. GR is designed to facilitate both real-time Augmented Reality (AR) and Virtual Reality (VR) applications on a variety of systems. Most of the underlying software methods are typically the same for both AR and VR and often the location of the operator is the only difference between the two.

Theoretical Paschen's Law Model For Aerospace Vehicles: Validation Experiment, Jaysen Mulligan Aroche

Electronic Theses and Dissertations

Aerospace vehicles often experience triboelectric charging while traversing the atmosphere. Triboelectric charging occurs when a material come into frictional contact with a different material. Aerospace vehicles triboelectrically charge due to frictional contact with dust and ice crystals suspended in the atmosphere. Launch vehicles traversing ice clouds in low-pressure atmosphere are especially prone to electrostatic discharge events (i.e. sparks). These conditions are hazardous and affect the vehicle's launch commit criteria. In 2010, engineers from an ARES-I rocket launch reported concerns with triboelectric charging over their self-destruct system antenna. This concern was addressed by putting the antenna through harsh conditions in a …

The Exploration Of Rotating Detonation Dynamics Incorporating A Coal-Based Fuel Mixture, John P. Rogan

Honors Undergraduate Theses

This investigation explores the detonation dynamics of a rotating detonation engine (RDE). Beginning with the general understanding and characteristics of hydrogen and compressed air as a detonation fuel source, this study further develops the experimental approach to incorporating a coal-based fuel mixture in an RDE. There is insufficient prior research investigating the use of coal as part of a fuel mixture and insignificant progress being made to improve thermal efficiency with deflagration. The U.S. Department of Energy's Office of Fossil Energy awarded the Propulsion and Energy Research Laboratory at the University of Central Florida a grant to lead the investigation …

A Novel Approach For Missing Combat Support Aircraft Search Acceleration Using Vtol Uas, Mohammed Ba Zuhair, Wisam Yousef, Issam Samara, Vladislav Varsegov

International Journal of Aviation, Aeronautics, and Aerospace

In this paper, an approach to accelerate search operations for a missing combat support aircraft using a portable waterproof autonomous vertical takeoff and landing unmanned aerial system called “flying locator beacon” is described. The latter is connected with both flight data and cockpit voice recorders with a parallel bus and may be deployed from the empennage during extreme emergency scenarios, which is detected when few flight parameters are overrun leading to an air crash stimulating behavior. Landing of the flying locator beacon strictly takes place on global latitude and longitude coordinates only of integer values enabling significant minimization of search …

Damage Characterization Of Aircraft Fuselage Using Vibrothermography Technique-Review And Analysis, Abbasali Saboktakin

International Journal of Aviation, Aeronautics, and Aerospace

Vibrothermogrphy is a promising non-destructive technique that uses ultrasonic elastic waves to detect damages and is typically applied in the aerospace and automotive industries. This technique allows for defect selective imaging using thermal waves that are generated by ultrasound waves. In this paper, vibrothermography technique was applied to the aircraft fuselage to detect its damage. The influence of the damage on the temperature distribution at the damage region on the aluminum was investigated by finite element technique. Comprehensive understanding in edge crack in fuselage heating caused by local friction between crack surfaces was obtained.

Dust Control Examination Using Computational Fluid Dynamics Modeling And Laboratory Testing Of Vortecone And Impingement Screen Filters, Ashish R. Kumar

Theses and Dissertations--Mining Engineering

Heavy industries, such as mining, generate dust in quantities that present an occupational health hazard. Prolonged exposure to the respirable dust has been found to result in many irreversible occupational ailments in thousands of miners. In underground mining applications, a variety of scrubbing systems are used to remove dust near the zones of generation. However, the wire-mesh type fibrous screens in the flooded-bed dust scrubbers used on continuous miners, are prone to clogging due to the accumulation of dust particles. This clogging results in a reduced capture efficiency and a higher exposure to the personnel. This research establishes the Vortecone, …

The Design Of A Rocket Propulsion Labview Data Acquisition And Control System, Dylan Allan Ott

Open Access Theses & Dissertations

When designing a rocket engine, both the propulsion system and propellant choice(s) are an important deciding factor. Desired rocket engine behavior, specific impulse, and levels of thrust are all different between the various propulsion systems. A bi-propellant cryogenic liquid 5lbf, 500lbf, and 2000lbf rocket engine was designed and manufactured by UTEP. The 5lbf rocket engine is a Reaction Control Engine and the 500lbf and 2000lbf rocket engine is a throttleable Main Engine. To provide a reliable and safe data acquisition and control system for this experiment, a Real-Time control platform was needed. A compact DAQ system was purchased and configured …

Adaptive Differential Thrust Methodology For Lateral/Directional Stability Of An Aircraft With A Completely Damaged Vertical Stabilizer, Long K. Lu, Kamran Turkoglu

Faculty Publications

This paper investigates the utilization of differential thrust to help a commercial aircraft with a damaged vertical stabilizer in order to regain its lateral/directional stability. In the event of an aircraft losing its vertical stabilizer, the consequential loss of the lateral/directional stability and control is likely to cause a fatal crash. In this paper, an aircraft with a completely damaged vertical stabilizer is investigated, and a unique differential thrust-based adaptive control approach is proposed to achieve a stable flight envelope. The propulsion dynamics of the aircraft is modeled as a system of differential equations with engine time constant and time …

Compressible Turbulent Flame Speed Of Highly Turbulent Standing Flames, Jonathan Sosa

Electronic Theses and Dissertations

This work presents the first measurement of turbulent burning velocities of a highly-turbulent compressible standing flame induced by shock-driven turbulence in a Turbulent Shock Tube. High-speed schlieren, chemiluminescence, PIV, and dynamic pressure measurements are made to quantify flame-turbulence interaction for high levels of turbulence at elevated temperatures and pressure. Distributions of turbulent velocities, vorticity and turbulent strain are provided for regions ahead and behind the standing flame. The turbulent flame speed is directly measured for the high-Mach standing turbulent flame. From measurements of the flame turbulent speed and turbulent Mach number, transition into a non-linear compressibility regime at turbulent Mach …

Development Of An Indoor Multirotor Testbed For Experimentation On Autonomous Guidance Strategies, Kidus Guye

Electronic Theses and Dissertations

Despite the vast popularity of rotary wing unmanned aerial vehicles and research centres that develop their guidance software, there are only a limited number of references that provide an exhaustive description of a step-by-step procedure to build-up a multirotor testbed. In response to such need, the first part of this thesis aims to describe, in detail, the complete procedure to establish and operate an autonomous multirotor unmanned aerial vehicle indoor experimental platform to test and validate guidance, navigation and control strategies. Both hardware and software aspects of the testbed are described to offer a complete understanding of the different aspects. …

Single Camera Photogrammetry Matlab Solver Developed For Automation Of The Oil Interferometry Process, Hunter Michael Dunn

Master's Theses

Over the last 20 years, Gregory G. Zilliac of the NASA AMES Research Center has been in continuous development of a fringe-imaging skin friction PC application used in oil interferometry analysis. This application, CXWIN5G, allows users to analyze propagation of oil smears across an aerodynamic surface using photogrammetry. The purpose of this thesis is to investigate the feasibility of increasing the level of automation currently found in CXWIN5G by developing a MATLAB solver capable of determining oil smear geometry with minimal user input.

There are two main automation goals of this thesis that are reflected in the core of the …

Simulation Of Non-Premixed Ethylene-Air Crossflow Jet Flame, Jennifer Onyinye Chikelu

Electronic Theses and Dissertations

Computational fluid dynamics tool has been employed in the past to determine and analyze efficiency or performance in combustion engines and for combustion analysis. This paper represents a systematic investigation on the best model predicts the temperature and soot production in coflow jet flame, by applying various RANS turbulent model, soot models and radiation models in presence or absence of gravity. It also applies this model predicted in crossflow jet flame and investigates the velocity ratio (ratio of the velocity of fuel jet to the velocity of air stream) variation effect on temperature and soot production. ANSYS-Fluent CFD software tool …

Iact Undergraduate Certificate In Applied Creativity (Year 1 - 2018), Brian Laduca

IACT Certificate Program

At the Institute of Applied Creativity for Transformation (IACT) at ArtStreet, we seek to empower a creatively confident 21st-century student with the ability to discover, invent and innovate ambiguous ideas through a disruptive design process that will impact today’s ever-changing global world regardless of degree focus.

IACT is home to the nation’s first undergraduate certificate in Applied Creativity for Transformation. Open to undergraduate students of any major, the certificate is a first step in achieving the University of Dayton’s vision of innovation, applied creativity, entrepreneurship and community engagement for the common good.

Development Of Ceramic 3d Printer Using Cold-Based Extrusion, Noah Naden

Summer Community of Scholars Posters (RCEU and HCR Combined Programs)

No abstract provided.

Radiation Effects In Tantalum Oxide-Based Resistive Memory Devices, Joshua Stuart Holt

Legacy Theses & Dissertations (2009 - 2024)

There is an increasing need for radiation-hardened electronics as space programs grow in number and scope. Scientific interest in long-term exploration, particularly in high-radiation environments such as Europa, as well as commercial interest in establishing permanent outposts, requires high tolerance of radiation effects. A flash memory device might survive for several years in low Earth orbit, but only a few days in orbit around Europa due to the extremely high levels of radiation encountered there. Meanwhile, commercial interests, including asteroid mining and building a base on the moon or Mars would require electronic systems that could survive for long periods …

Mechanical Wear Debris Feature, Detection, And Diagnosis: A Review, Wei Hong, Wenjian Cai, Shaoping Wang, Mileta M. Tomovic

Engineering Technology Faculty Publications

Mechanical debris is an important product of friction wear, which is also a crucial approach to know the running status of a machine. Many studies have been conducted on mechanical debris in related fields such as tribology, instrument, and diagnosis. This paper presents a comprehensive review of these studies, which summarizes wear mechanisms (e.g., abrasive wear, fatigue wear, and adhesive wear) and debris features (e.g., concentration (number), size, morphology, and composition), analyzes detection methods principles (e.g., offline: spectrograph and ferrograph, and online: optical method, inductive method, resistive-capacitive method, and acoustic method), reviews developments of online inductive methods, and investigates the …

Strong Stability Of A Class Of Difference Equations Of Continuous Time And Structured Singular Value Problem, Qian Ma, Keqin Gu, Narges Choubedar

SIUE Faculty Research, Scholarship, and Creative Activity

This article studies the strong stability of scalar difference equations of continuous time in which the delays are sums of a number of independent parameters tau_i, i = 1, 2, . . . ,K. The characteristic quasipolynomial of such an equation is a multilinear function of exp(-tau_i s). It is known that the characteristic quasipolynomial of any difference equation set in the form of one-delayper- scalar-channel (ODPSC) model is also in such a multilinear form. However, it is shown in this article that some multilinear forms of quasipolynomials are not characteristic quasipolynomials of any ODPSC difference equation set. The equivalence …