Engineering Commons^™

Hot Wire Anemoteter, Michael S. Potash, Albert D. Helfrick

Publications

A hot wire anemometer circuit has a calibrate subcircuit and an operate subcircuit which are selectively invoked via a user-activate mode switch. The calibrate subcircuit includes a detector configured to compare an amplified sensor voltage with an amplified drive voltage and output an indicator signal when the two voltages match. The drive voltage is derived from a user-adjusted drive resistance of a bridge subcircuit. The operate circuit includes a feedback loop which provides a signal to a bride node of a bridge circuit. After a sensor is connected to the anemometer circuit, the drive resistance is adjusted until the indicator …

Standardization Roadmap For Unmanned Aircraft Systems, Version 1.0, Kristine Kiernan, Christian Janke, Kenneth Witcher

Publications

This Standardization Roadmap for Unmanned Aircraft Systems, Version 1.0 (“roadmap”) represents the culmination of the UASSC’s work to identify existing standards and standards in development, assess gaps, and make recommendations for priority areas where there is a perceived need for additional standardization and/or pre-standardization R&D.

The roadmap has examined 64 issue areas, identified a total of 60 gaps and corresponding recommendations across the topical areas of airworthiness; flight operations (both general concerns and application-specific ones including critical infrastructure inspections, commercial services, and public safety operations); and personnel training, qualifications, and certification. Of that total, 40 gaps/recommendations have been identified as …

A Remote Observatory For Geocoronal Hydrogen Emissions, Margaret A. Gallant

Doctoral Dissertations and Master's Theses

The Investigating Near Space Interaction Regions (INSpIRe) observatory is an adapt- able research facility that is designed to use Fabry-Perot interferometer (FPI) to study the faint Balmer series emissions of the terrestrial upper thermosphere and exosphere, collectively known as the geocorona. This instrumentation is designed to be deployable to a clear-air site, necessitating remote operations of the entire observatory, including control and monitoring. The facility currently employs a siderostat to allow for pointing at sky targets, a pressure-tuned dual-etalon FPI to allow for high spectral resolution (R_80,000) measurements, and several charge-coupled device (CCD) imagers for guiding and collecting data. The …

Control Driven Scaling Effects Of Motor And Rotors For Urban Air Mobility Design, Agustin A. Giovagnoli

Doctoral Dissertations and Master's Theses

Through this thesis research the problem of controllability and propulsion associated with scaling-up consumer drones to vehicles that may carry significantly larger payloads, including passenger will be analyzed and tested. Controllability is mainly compromised due to the increasing response time of a larger rpm controlled rotor. This requires a more powerful motor, which translates into heavier and larger devices compromising the thrust-to-weight ratio. Collective pitch control at constant rpm is proposed as a first approach to mitigate the controllability problem, and it is tested in a MATLAB Simulink environment. This solution, linked to a Non-linear Dynamic Inversion controller, is simulated …

Design Of An Attitude Control System For A Spacecraft With Propellant Slosh Dynamics, Nolan Coulter

Doctoral Dissertations and Master's Theses

The presence of propellant slosh dynamics in a spacecraft system during a maneuver leads to attitude control system (ACS) performance degradation resulting in attitude tracking errors and instability. As spacecraft missions become more complex and involve longer durations, a substantial propellant mass is required to achieve the mission objectives and perform orbital maneuvers. When the propellant tanks are only partially filled, the liquid fuel moves inside the tanks with translational and rotational accelerations generating the slosh dynamics. This research effort performs a comparative study with different optimal control techniques and a novel application of a model reference artificial immune system …

Shape-Stabilization Of Pcm/Hdpe Composites With 3d-Printing Applications For Battery Thermal Management, Thomas Benjamin Freeman

Doctoral Dissertations and Master's Theses

Phase-change materials (PCMs) are a useful alternative to more traditional methods of thermal management of Li-ion batteries in electric or hybrid-electric vehicles. PCMs are materials which absorb large amounts of latent heat and undergo solid-to-liquid phase change at near-constant temperature. The goal of this thesis is to experimentally investigate the thermal properties of a novel shape-stabilized PCM/HDPE composite extruded filament. The extruded filament can then be used in a 3D printer for custom PCM/HDPE shapes. These custom PCM/HDPE shapes can be used to help reduce weight, energy consumption, and complexity of the thermal management of the ESS. The PCM used …

Design And Implementation Of Intelligent Guidance Algorithms For Uav Mission Protection, Karina Rivera

Doctoral Dissertations and Master's Theses

In recent years, the interest of investigating intelligent systems for Unmanned Aerial Vehicles (UAVs) have increased in popularity due to their large range of capabilities such as on-line obstacle avoidance, autonomy, search and rescue, fast prototyping and integration in the National Air Space (NAS). Many research efforts currently focus on system robustness against uncertainties but do not consider the probability of readjusting tasks based on the remaining resources to successfully complete the mission. In this thesis, an intelligent algorithm approach is proposed along with decision-making capabilities to enhance UAVs post-failure performance. This intelligent algorithm integrates a set of path planning …

Systems And Methods For Noise Mitigation For Hybrid And Electric Aircraft, Lenny Gartenberg, Richard P. Anderson, Borja Martos

Publications

A system and method of noise mitigation for hybrid and electric aircraft, the aircraft having a controllable pitch propeller or rotor(s) with a plurality of blades. The propeller or rotor(s) are driven by a drive system to provide thrust for the aircraft, and the blades of the propeller or rotor(s) are further movable about pivot axis to vary a pitch thereof. A controller on-board the aircraft is operable to cause rotation or movement of the blades of the propeller or rotor(s) about their pivot axis to alter and/or focus at least one aspect of the propeller generated noise to reduce …

Digital Disruption Solution, Camila Bisinoto Borges, Cristiane Lunardi Das Neves Rodriques, Daniel Dias Landroni, Tatiane De Araugo Mendonça

Graduate Student Works

Since March, 2017, the cost of denied boarding began to draw the attention of all Brazilian airlines because of the Resolution 400 of the Brazilian National Civil Aviation Agency. This Resolution covers several items but here we will focus on the penalty that the airlines need to pay for each passenger who had his boarding denied involuntarily in domestic flights.

An operating restriction of an airline may result in the denial of boarding of a specified number of passengers. When this process of selecting the passengers and their accommodation on another flight happens very close to the time of departure, …

Financial Evaluation For A Brazilian Airline To Conduct Aeronautical Components Repair In Brazil, Ana Moreno Sandoval, Enzo Canavesi Luizetto, Joao Paulo Panssiera, Klaus Goulart Brum

Graduate Student Works

The current economic world volatility, as well as the increasing cost of fuel and security procedures established by the worldwide authorities, force the air carriers to search for alternatives to reduce their operational costs. The maintenance costs are a significant subject for the air carriers, therefore, any cost reduction obtained without maintenance service disruption, may provide an opportunity to enhance the airline competitiveness (Fritzsche, 2014).

The purpose of this research is to evaluate and compare the technical and financial aspects of performing aircraft components repair in house for a Brazilian airline versus outsourcing the servicing to a homologated company outside …

Vortex Structures Inside Spherical Mesoscopic Superconductor Plus Magnetic Dipole, A. Ludu

Publications

We investigate the existence of multivortex states in a superconducting mesoscopic sphere with a magnetic dipole placed at the center. We obtain analytic solutions for the order parameter inside the sphere through the linearized Ginzburg-Landau (GL) model, coupled with mixed boundary conditions, and under regularity conditions and decoupling coordinates approximation. The solutions of the linear GL equation are obtained in terms of Heun double confluent functions, in dipole coordinates symmetry. The analyticity of the solutions and the associated eigenproblem are discussed thoroughly. We minimize the free energy for the fully nonlinear GL system by using linear combinations of linear analytic …

Erosion Rate Equations For Coarse- Grained Materials Using A Small Flume Testing, Ghada Ellithy, Johannes L. Wibowo, Maureen K. Corcoran

Publications

Erosion rate of soils during a levee or dam overtopping event is a major component in risk assessment evaluation of breach time and consequently in determining the downstream consequences. There is uncertainty in estimation of the erosion rate especially for coarsegrained materials that comprise the outer shell layer of dams as well as homogenous levees that are constructed of such materials. In this paper, erosion rate results are presented on three soil mixes that share the same median grain size D50 of 2 mm, the fines content varies between zero and 20%, and the gravel content between zero and 30%. …

A Numerical And Experimental Evaluation Of The Turbulent Heat Flux In A Heated Jet In Crossflow, Michael R. Borghi Jr.

Doctoral Dissertations and Master's Theses

The injection of fully-developed turbulent heated air from a tube into a cooler turbulent duct flow is examined, as an analogy to film cooled turbine blades. Scale Resolving Simulations (SRS) are used to examine the flow numerically. A Detached Eddy Simulation (DES) methodology is examined but found to be ineffective at correctly capturing the physics of the flow. A Large Eddy Simulation (LES) numerical model is developed and applied in which tube and duct turbulence inflow effects are emulated using a divergence-free synthetic eddy method (SEM). The LES sensitivity to the synthetic inflow turbulence is examined with a series of …

Topology Optimization Using Load Path And Homogenization, Kaveh Gharibi

Doctoral Dissertations and Master's Theses

In this work, the connection between topology optimization and load transfer has been established. New methods for determining load paths in two dimensional structures, plates and shells are introduced. In the two-dimensional space, there are two load paths with their total derivative equal to the transferred load, their partial derivatives related to stress tensor, and satisfying equilibrium. In the presence of a body load the stress tensor can be decomposed into solenoidal and irrotational fields using Gurtin or Helmholtz decomposition. The load path is calculated using the solenoidal field. A novel method for topology optimization using load paths and total …

Direct Adaptive Control For A Trajectory Tracking Uav, Nirmit Prabhakar

Doctoral Dissertations and Master's Theses

This research focuses on the theoretical development and analysis of a direct adaptive control algorithm to enable a fixed-wing UAV to track reference trajectories while in the presence of persistent external disturbances. A typical application of this work is autonomous flight through urban environments, where reference trajectories would be provided by a path planning algorithm and the vehicle would be subjected to significant wind gust disturbances. Full 6-DOF nonlinear and linear UAV simulation models are developed and used to study the performance of the direct adaptive control system for various scenarios. A stability proof is developed to prove convergence of …

Variable Fidelity Studies In Wake Vortex Evolution, Safety, And Control, Petr Kazarin

Doctoral Dissertations and Master's Theses

The purpose of this research is to develop a variable-fidelity approach for addressing the safety of unmanned aerial system (UAS) operations in the national aerospace system (NAS). This task is implemented on the basis of safety investigation toolkit for analysis and reporting wake vortex safety system (SITAR WVSS) code, which is a dynamic low-fidelity model addressing generation, evolution, and interaction of the leader-aircraft wake vortex with the follower-aircraft lifting surfaces.

The first part of the dissertation deals with the generation, evolution, and interaction of the wake vortices produced by an aircraft. In particular, it presents the results of the vortex …

Challenges For Flight Instructors Teaching Weather Information, Robert Thomas, Thomas A. Guinn

Aviation Weather Training Research

• Flight Instructors face a challenge when teaching/learning weather information
• Multiple overlapping resources for aviation weather
• AC takes longer timeframe to update –problem for quick updates of information

Assessing Ga Pilots' Preflight Weather Planning Mental Models, Yolanda Ortiz, Beth Blickensderfer, Thomas A. Guinn

General Aviation Weather Display Interpretation

Purpose, To assess GA Pilots' ability to:

• Obtain the Appropriate Weather Information
• Interpret the Data
• Apply the Information to a Given Flight Route

Interpreting Aviation Weather Products: Follow-Up Study With Aopa Members, Beth Blickensderfer, Thomas A. Guinn, Thomas Bob, Jayde King, Yolanda Ortiz, Nick Defilippis, Quirijn Berendschot, Jacqueline Mcsorley

General Aviation Weather Display Interpretation

Purpose

• Use the questions we developed in Phase I
• Include pilots that are more representative of GA (age, flight hours/experience); Collaborate with AOPA
• Examine: Knowledge about aviation weather products; Differences between levels of flight certificate and/or ratings

Aviation Weather Education: Challenges Using Current Faa Guidance, Thomas A. Guinn, Robert Thomas

Aviation Weather Training Research

Observed Challenges

• Incorrect product information
• Guidance not keeping pace with new products
• Multiple formats of same product
• Potentially unnecessary information
• Missing product information
• Limited focus on interpretation

A New Framework For Securing, Extracting And Analyzing Big Forensic Data, Hitesh Sachdev, Hayden Wimmer, Lei Chen, Carl Rebman

Journal of Digital Forensics, Security and Law

Finding new methods to investigate criminal activities, behaviors, and responsibilities has always been a challenge for forensic research. Advances in big data, technology, and increased capabilities of smartphones has contributed to the demand for modern techniques of examination. Smartphones are ubiquitous, transformative, and have become a goldmine for forensics research. Given the right tools and research methods investigating agencies can help crack almost any illegal activity using smartphones. This paper focuses on conducting forensic analysis in exposing a terrorist or criminal network and introduces a new Big Forensic Data Framework model where different technologies of Hadoop and EnCase software are …

Information Technology System Failure And Value Of Airlines: A Case Study Of Airlines In 2016, Jayendra Gokhale

Publications

Technology is a critical component of a firm’s operations. Technology failures can cause widespread problems in airlines. These failures cause disruptions in flight schedules, cause passengers to be stranded at airports and also increase airline operating costs. The objective of this study is to measure an effect of information technology failures on the firm value of passenger airline companies during the year 2016. In that year, there were cases involving delays and cancellations associated with JetBlue, Southwest, Delta, American, and Virgin America that received significant media coverage. Using the event study methodology, this study finds that the intensity of failures …

Does Length Of Ride, Gender Or Nationality Affect Willingness To Ride In A Driverless Ambulance?, Stephen Rice, Scott R. Winter, Rian Mehta, Joseph R. Keebler, Bradley S. Baugh, Emily C. Anania, Mattie N. Milner

Publications

Due to the frequent lack of ambulances and personnel, the purpose of this study was to examine consumers’ willingness-to-ride in an ambulance that was either driven by a human driver or completely automated (with no human driver) based on the gender of the participant and their nationality, either Indian or American. A two-study experimental design was utilized using over 1,000 participants. In Study 1, the length of the ride and the type of driver were manipulated while in Study 2, the length of the ride was manipulated across genders and nationality. Study 2 also collected affect measures to complete a …

Hybrid Magneto-Active Propellant Management Device For Active Slosh Damping Within A Vehicle Fuel Tank, Balaji Sivasubramanian, Leander Paul, Sathya Gangadharan

Publications

This disclosure includes a hybrid magneto-active mem­brane, which can be used as part of a Magneto-active Propellant Management Device (MAPMD), to actively con­trol free surface effects of liquid materials, such as fuels, and to reduce fuel slosh. The disclosed MAPMD merges aspects of a diaphragm membrane with a magneto-active inlay to control the membrane during in-flight conditions.

Floating Active Baffles, System And Method Of Slosh Damping Comprising The Same, Dae Won Kim, Rudy L. Baum, Vijay Santhanam, Balaji Sivasubramanian, Sathya Gangadharan

Publications

This disclosure provides a system for damping slosh of a liquid within a tank, a baffle for use in the system, and a method of damping slosh using the system. The system includes a plurality of baffles. Each baffle has a body configured to substantially float upon the liquid. Each baffle also has an activation material received along at least a portion of the body. The activation material is magnetically reactive provided in a quantity sufficient to enable the body to be manipulated in the presence of a magnetic field (M). The system further includes an actuator configured to pro­vide …

Hybrid Magneto-Active Propellant Management Device For Active Slosh Damping Within A Vehicle Fuel Tank, Balaji Sivasubramanian, Leander Paul, Sathya Gangadharan

Publications

This disclosure includes a hybrid magneto-active mem­brane, which can be used as part of a Magneto-active Propellant Management Device (MAPMD), to actively con­trol free surface effects of liquid materials, such as fuels, and to reduce fuel slosh. The disclosed MAPMD merges aspects of a diaphragm membrane with a magneto-active inlay to control the membrane during in-flight conditions.

A Comparison Of Special Category Light-Sport And Corresponding Type-Certificated Aircraft Safety, Carolina Anderson, Alan Stolzer, Douglas D. Boyd

Publications

The special category light sport airplane (light sport) sector of general aviation has grown 10-fold in as many years with solo operations requiring only a sports pilot's certificate. With little research on light sport airplane safety, the study objective was to compare light sport and type-certificated airplane accident rates.

Accidents were identified from the National Transportation Safety Board database. Statistics employed Poisson distribution/proportion analyses/Mann–Whitney U-tests.

For the 2009–2015 period, the light sport airplane accident rate (fatal/non-fatal combined) was > 15-fold higher than comparable type-certificated aircraft, undiminished over time. The excessive light sport airplane accident rate was associated with inferior airman experience …

Application Of Dupont’S Dirty Dozen Framework To Commercial Aviation Maintenance Incidents, Greg M. Mellema

Doctoral Dissertations and Master's Theses

This study examined the 12 preconditions for maintenance errors commonly known as the Dirty Dozen and applied them to actual incident and accident data provided by a participating airline (PA). The data provided by the PA consisted of Maintenance Event Reports (MERs) (reactive), Maintenance Operations Safety Assessment (MOSA) reports (proactive), and the results of the 2017 Maintenance Climate Awareness Survey (MCAS) (subjective). The MER and MOSA reports were coded by aviation maintenance subject matter experts (SMEs) using the 12 Dirty Dozen categories as the coding scheme, while the MCAS responses were parsed according to the precondition category they best represented. …

Identifying Criteria To Predict Army Rifle Marksmanship Proficiency, Katlin Makina Anglin

Doctoral Dissertations and Master's Theses

The United States Army requires each Soldier to develop marksmanship proficiency in an effort to achieve combat readiness. Soldiers currently develop marksmanship proficiency through Basic Rifle Marksmanship (BRM) training, but significant skill deficiencies are apparent at the end of training. These skill deficiencies remain throughout training because instructors rarely assess Soldiers objectively before the final qualification, reducing the opportunity for instructors to diagnose skill deficiencies until it is too late. Therefore, the goal of the current research is to identify individual differences and sensor-based performance measures for inclusion in a formative assessment during BRM training. The results of the current …

An Analysis Of Cabin Ozone Regulations, Taylor L. Pottinger, Cheryl L. Marcham

Publications

Exposure to elevated levels of ozone have been reported to be associated with complaints of discomfort such as dry mouth, eye irritation and dryness, nasal irritation coughing, and headaches. The Federal Aviation Administration (FAA) established regulatory requirements in 1980 to limit cabin ozone levels to no more than 0.25 parts per million (ppm) at any time or 0.1 ppm averaged over a 3-hour interval for any flight over four hours in length. The FAA also published an Advisory Circular (AC), AC 120-38, to provide guidance to air carriers on how to comply with these then new ozone regulations. Methods of …