Engineering Commons^™

Robust Nonlinear Estimation And Control Applications Using Synthetic Jet Actuators, Natalie Ramos Pedroza

Doctoral Dissertations and Master's Theses

Limit cycle oscillations (LCO), also known as utter, cause significant challenges in flight control of small unmanned aerial vehicles (SUAVs), and could potentially lead to structural damage and catastrophic failures. LCO can be described as vibrational motions in the rocking, pitching and plunging displacements of an aircraft wing. To address this, the use of synthetic jet actuators (SJAs) in UAV flight control systems is becoming popular as a practical alternative and to mechanical deflection surfaces.

Synthetic jet actuators are promising tools for LCO suppression systems in small UAVs due to their small size, ease of operation, and low cost. Uncertainties …

Design And Optimization Of Aircraft Configuration For Minimum Drag, Zin Win Thu, Aung Myo Thu, Phyo Wai Thaw

International Journal of Aviation, Aeronautics, and Aerospace

This paper presents a reliable and robust optimization for minimum drag of an aircraft at the conceptual design phase. Firstly, the conceptual design code was developed and existing Single Seat Aerobatic (SSA) aircraft was chosen to validate the reliability of developed code. The resulted data from the developed code showed good agreement with the existing data. Secondly, Sequential Quadratic Programming (SQP) optimizer was created and employed as a tool to explore possible aircraft configurations that are more efficient and less costly than an existing design. The optimized results gave lower Drag and better performance.

Mental Health In Commercial Aviation - Depression & Anxiety Of Pilots, Maurice C. Dehoff, Stephen K. Cusick

International Journal of Aviation, Aeronautics, and Aerospace

Two landmark accidents invigorated the discussion regarding pilot mental health. Other incidents may also have a mental health component that is related to, but not the direct cause of, the event. It is suspected that these “other incidents” are much more commonplace and while not catastrophic, erode safety. Depression and anxiety are two commonly occurring mental health concerns. Research indicates that a considerable portion of the U. S. population suffers from some form of mental health issue. Most go undiagnosed and untreated. A similar rate of occurrence appears to be found within the airline pilot population. The stigma of mental …

Called To Safety? Individual And Combined Effects Of Safety Climate And Occupational Callings On Aviator Safety Performance, Michele W. Gazica, Erin E. Bowen, Michael A. Mccarson, Kristen A-M. Chadwell

Journal of Aviation/Aerospace Education & Research

This study examined the individual and combined effects of two potential antecedents to aviation-related safety performance: safety climate and occupational callings. Research exploring the importance of occupational callings to the safety domain is in its nascent stages. The extent that someone is living a calling may explain variance in actual safety performance above that which can be explained by safety climate alone. Survey data from aviators in a flight training program were analyzed to evaluate the ability of occupational calling assessments to inform the potential for safety mishaps within the aviation industry. Results indicate that both safety climate and occupational …

Adaptive Learning Pedagogy Of Universal Design For Learning (Udl) For Multimodal Training, Ziho Kang, Mattlyn R. Dragoo, Lauren Yeagle, Randa L. Shehab, Han Yuan, Lei Ding, Stephen G. West

Journal of Aviation/Aerospace Education & Research

Traditionally, students or trainees usually receive training through a unidirectional instructional approach that can lack interactive activities or through a single material source in classrooms. Therefore, it is possible that some trainees might encounter a sink-or-swim situation if they are not able to understand the materials presented during classroom lectures nor execute correct procedures during laboratory sessions with time-intensive training. To address this issue, the Universal Design for Learning (UDL) asserts that trainees can increase their performance if instructors can provide the trainees with diversified means of information representation, expression opportunities, and engagement means. However, we lack the framework on …

Human Error Analysis Of Helicopter Emergency Medical Services (Hems) Accidents Using The Human Factors Analysis And Classification System (Hfacs), Paul E. Cline

Journal of Aviation/Aerospace Education & Research

Helicopter Emergency Medical Services (HEMS) is among the most dangerous type of flying in commercial aviation. This research utilized the Human Factors Analysis and Classification System (HFACS) to understand the errors, preconditions and violations that contribute to these accidents. Drawing upon source data from the National Transportation Safety Board’s Aviation Accident Database, HEMS accidents from 2000-2016 were analyzed according to the HFACS framework.

Take-Off Characteristics For Naca 4612 Aerofoil In A Twin-Wing Configuration With Optimum Angles Of Attack, Elena Vishnevskaya, Kenneth L. Witcher, Ian R. Mcandrew

Publications

Unmanned Aerial Vehicles are used generally at low levels and speeds. The research reported in this article investigates the possible use of twin-wing designs for higher altitudes with a focus on the possible lift capable for either short runways or high payloads. The wing aerofoil and unique Angles of Attack, AoA, are set 5o on the upper wing and 10o on the lower. There is a positive upper wing stagger of 50% of the chord length at height separation of 1 chord. These parameters have been established from previous research and this research investigates how they generate lift at take-off …

Airships In U.N. Humanitarian And Peace Operations: Ready For Service?, Walter Dorn, Nic Baird, Robert Owen

Journal of Aviation/Aerospace Education & Research

This study examines whether the United Nations should take steps in the near future to exploit the operational characteristics of lighter-than-air (LTA) and hybrid aircraft in support of its peace and humanitarian operations. Continued progress in the development of LTA transport system makes this a timely issue. At the same time, this progress highlights persistent challenges to the conduct of reliable and safe LTA operations, particularly in the face of bad weather and threats from groups hostile to the UN mission. The report examines this issue in four sections: (1) the potential advantages of LTA operations; (2) their disadvantages; (3) …

Meeting Real World Demands Of The Global Economy: An Employer's Perspective, Doreen Mcgunagle, Laura Zizka

Journal of Aviation/Aerospace Education & Research

Educational programs prepare students theoretically for the workplace, but many programs are still lacking in the real-world skills that the workplace requires. This is especially evident in Science, Technology, Engineering, and Math (STEM) education where today’s graduates hold a fundamental role in advancing science, medicine, sustainability, national security, and the economy, yet the programs to prepare them are falling short of employer expectations. At present, there is a lack of information on the necessary skills for workplace success that is specific to Airline, Aerospace, Defense (A&D) and related Industries’ STEM graduates. This paper attempts to fill this gap by offering …

Infographic : Engineers And Athletes: Career Opportunities And Average Earnings, Mckenna James, Leroy Long Iii

Publications

In this infographic, the average earnings for athletes and engineers are displayed. For a variety of sports, the average yearly salary, average career length, and average career earnings are collected. In a similar way, the average mid-career salary and average career earnings are shown for multiple engineering disciplines. In addition, a series of facts show the professional opportunities for engineers and athletes. Based on this infographic, engineering is a more viable career choice and competes with the career earnings of professional athletes. This infographic is not meant to discourage playing sports, but to encourage youth and young adults to view …

Evaluating The Effect Of Turbulence On Aircraft During Landing And Take-Off Phases, Anthony O' Connor, Derek Kearney

International Journal of Aviation, Aeronautics, and Aerospace

—— Low level wind shear and turbulence present a serious safety risk to aircraft during the approach, landing and take-off phases. Low level wind shear has been identified as one of the primary factors for aircraft go-arounds and aborted landings. During any given year, wind shear occurs thousands of times at airports around the world, affecting the arrival and departure of aircraft. This paper has quantified the direct cost of flight Go-arounds. This paper will show the potential savings to the aviation industry. This paper will argue that a solution to the problem of forecasting low level wind shear and …

Design Of Revising Proximity Between Space And Time Cues On Flight Deck Displays To Support Nextgen – The First Phase, Chang-Geun Oh, Jennie J. Gallimore, Pamela S. Tsang

International Journal of Aviation, Aeronautics, and Aerospace

The objective of this study is to develop and evaluate novel display formats to support RTA operations for near to midterm NextGen. Traditional cockpit displays separate space and time information in distant display sources in heterogeneous formats (graphics vs. text). This design composition may cause potential pilot errors when required time of arrival (RTA) obligations are imposed at every waypoint in NextGen. Pilots were randomly assigned to four different display conditions in a simulator – one traditional display with distant space and time cues, and three novel displays with close spatial proximity between the two cues. In the first phase …

Evaluating Small Uas Near Midair Collision Risk Using Aeroscope And Ads-B, Ryan J. Wallace, Kristy W. Kiernan, Tom Haritos, John Robbins, Godfrey V. D'Souza

International Journal of Aviation, Aeronautics, and Aerospace

As small unmanned aircraft systems (sUAS) continue to proliferate in the National Airspace System (NAS), near midair collisions are becoming more common. In late 2017, the National Transportation Safety Board released a report detailing the first confirmed midair collision between a sUAS and manned aircraft in the United States. In February 2018, a video of a sUAS maneuvering around a passenger jetliner on approach to a Las Vegas airport went viral on YouTube. Just months later, a helicopter instructor pilot reported performing evasive maneuvers to avoid colliding with a sUAS, resulting in a non-fatal crash. From 2014 to 2018 the …

Manned Versus Unmanned Aircraft Accidents, Including Causation And Rates, Justin A. Jaussi, Herbert O. Hoffmann

International Journal of Aviation, Aeronautics, and Aerospace

Many consider aircraft reliability a primary deterrent to the further integration of unmanned aircraft into civil airspace. Discussions of unmanned aircraft reliability often include comparisons of accident rates of medium and large unmanned aircraft (like the MQ-1 Predator and MQ-9 Reaper) to those of manned aircraft. These comparisons, however, often consider a recent period only but do not consider platform maturity. While this approach is valid—and worthy of discussion—it does not present a complete picture of the unmanned aircraft safety record. This paper employs a chi-square goodness-of-fit approach to compare the progression of the U.S. Air Force MQ-9 mishap rate …

Design Of Revising Proximity Between Space And Time Cues On Flight Deck Displays To Support Nextgen – The Second Phase, Chang-Geun Oh, Jennie J. Gallimore, Pamela S. Tsang

International Journal of Aviation, Aeronautics, and Aerospace

The prior first phase of this study investigated the effectiveness of new design of flight deck display for required time of arrival operation of NextGen by collecting objective query response data during autopilot flights and subjective data about the perception between display condition and situation awareness level. To evaluate pilots’ mental workload during the operations when they interacted with novel flight deck display design, this second phase provided pilots with simulation flight tasks arriving at four successive waypoints on time in the same display conditions as the first phase and asked them to rate their mental workload ratings. The workload …

Assessing The Risks: An Analysis Of Wildlife-Strike Data At The Three Busiest Brazilian Airports (2011-2016), Flavio A. C. Mendonca Ph.D., Chenyu Huang Ph.D., Thomas Q. Carney Ph.D., Mary E. Johnson Ph.D.

International Journal of Aviation, Aeronautics, and Aerospace

Brazil is the largest country in Latin America and has a considerable amount of air traffic volume domestically and internationally. Wildlife strikes are an increasing safety and economic concern for aviation operations in Brazil. The Brazilian Aeronautical Accidents Investigation and Prevention Center (CENIPA) has published annual reports summarizing the results of analyses of the data in a national level since 2009. The goal of this study was to supplement the CENIPA’s annual reports with information derived from the analysis of wildlife strikes to aviation, during 2011-2016, from the three busiest international commercial airports in Brazil: Guarulhos, Brasília, and Galeão. A …

Entrepreneurial Mindset: Integrating Creative Thinking And Innovation Into A Graphical Communications Course, Leroy Long Iii, Lulu Sun

Publications

Nationwide, leaders in business and industry have increasingly acknowledged the importance of entre¬preneurship. Several areas of the country showcase the importance of entrepreneurship such as Silicon Valley in California where a large number of start-up companies in science, technology, engineering and math (STEM) fields are located. To meet the needs of business and industry, institutions of higher educa¬tion prepare students for future employment by offering rigorous and relevant coursework in areas such as entrepreneurship. Collegiate faculty and staff can use fundamental engineering courses to instill an en¬trepreneurial mindset – a set of beliefs, attitudes, and behaviors that drive innovation – …

Infographic: Institutional Barriers To Black And Latino Male Collegians’ Success In Engineering And Related Stem Fields, Leroy L. Long Iii, William Wanyagah

Publications

Infographic was created to support the article Institutional Barriers to Black and Latino Male Collegian's Success in Engineering and Related Stem Fields, which can be read here:

Research Of Sustainable Jet Fuel Production Using Microbes, Rajee Olaganathan

Publications

Global climate change, coupled with rapidly increasing oil prices and energy demand around the world, has paved a way for intense research in the biofuel sector. Stakeholders in the aviation industry have started to focus on bio-jet fuel. Bio-jet fuel is regarded as a sustainable solution to greenhouse gas emissions and energy demand. This paper provides a brief review of the biofuel production technologies, the role of bacteria in producing hydrocarbons and the recent advancements in microbial engineering to enhance the biofuel production. Finally, this paper concludes by highlighting the challenges and future research implications in bio-jet fuel production.

Commercial Airline Pilots' Attitudinal Data On Controlled Rest In Position: A Qualitative Inquiry, Stephen Rice, Scott R. Winter, Emily C. Anania, Gajapriya Tamilselvan, Shawn Doherty

Publications

Fatigue is a significant contributor to accidents in aviation, in commercial, private, and military aircraft, and is defined as “extreme tiredness resulting from mental or physical exertion or illness” (Oxford Dictionary, 2017, n.p.). Typical fatigue mitigation techniques include work and rest scheduling, obtaining required minimum rest before a flight, and pharmacological countermeasures (Caldwell & Caldwell, 2005; Caldwell, Mallis, Caldwell, Paul, Miller, & Neri, 2009). However, Controlled Rest in Position (CRIP), or in-flight sleep, may be another potential way to mitigate pilot fatigue. Prior research has investigated consumer perceptions relating to CRIP, revealing unfavorable perceptions (Winter, Carryl, & Rice, 2015). However, …

Uas Pilots Code – Annotated Version 1.0, Michael S. Baum, Kristine Kiernan, Donald W. Steinman, Ryan J. Wallace Ed.D.

Publications

The UAS PILOTS CODE (UASPC) offers recommendations to advance flight safety, ground safety, airmanship, and professionalism.6 It presents a vision of excellence for UAS pilots and operators, and includes general guidance for all types of UAS. The UASPC offers broad guidance—a set of values—to help a pilot interpret and apply standards and regulations, and to confront real world challenges to avoid incidents and accidents. It is designed to help UAS pilots develop standard operating procedures (SOPs), effective risk management,7 safety management systems (SMS), and to encourage UAS pilots to consider themselves aviators and participants in the broader aviation community.

Synthetic Jet Actuator-Based Aircraft Tracking Using A Continuous Robust Nonlinear Control Strategy, N. Ramos-Pedroza, W. Mackunis, M. Reyhanoglu

Publications

A robust nonlinear control law that achieves trajectory tracking control for unmanned aerial vehicles (UAVs) equipped with synthetic jet actuators (SJAs) is presented in this paper. A key challenge in the control design is that the dynamic characteristics of SJAs are nonlinear and contain parametric uncertainty. The challenge resulting from the uncertain SJA actuator parameters is mitigated via innovative algebraic manipulation in the tracking error system derivation along with a robust nonlinear control law employing constant SJA parameter estimates. A key contribution of the paper is a rigorous analysis of the range of SJA actuator parameter uncertainty within which asymptotic …

Highly Vented Truss Wall Honeycomb Structures, David J. Sypeck

Publications

A vented honeycomb structure with a plurality of honeycomb cells arranged in a hierarchical order and having a plurality of truss walls, each truss wall including a plurality of members. The vented honeycomb structure is fabricated by joining a plurality of sheets of trusses using any one of an expansion, a corrugation, and a slotting process. Fabrication can also occur by deposition, casting, additive, extrusion, or aligning and joining methods. The honeycomb cells, truss walls, truss wall openings, and truss wall members can be functionally graded.

Optimized Thruster Allocation Utilizing Dual Quaternions For The Asteroid Sample Return Mission (Osiris-Rex), Asher Smith

Doctoral Dissertations and Master's Theses

As spacecraft require higher positional accuracy from the attitude control systems, new algorithm developments, along with sensor and actuator resolution and range improvements are necessary to achieve the desired science accuracies. For agile 6-Degrees of freedom (6-DOF) spacecraft with redundancy, the actuators are usually oversized or overpopulated to meet the desired slew requirements. Currently, most spacecraft utilize an over-actuated thruster system to produce 6-DOF control. This thesis presents a simulation of the OSIRIS-REx mission during the descent phase to the asteroid Bennu, with a focus on utilizing dual quaternion dynamics and a newly developed thruster allocation method. The dual quaternion …

Low-Cost Wearable Head-Up Display For Flight General Aviation, Pavan K. Chinta

Doctoral Dissertations and Master's Theses

A low-cost wearable Commercial-off-The-Shelf (COTS) Augmented Reality (AR) Head-Up Display (HUD) system is designed, successfully reduced to practice, and flight tested. The system is developed based on the need for a technology that improves loss-of-control (LOC) safety in the General Aviation (GA) sector. The accuracy of the flight-path based system is determined to be within a degree of the truth source. The repeatability of the data from the COTS system is excellent. A complementary filter is proposed for air data flow angles and successfully flight tested for straight and level flight, dynamic maneuvering, and atmospheric turbulence, provided that a reasonably …

Mechanical And Electrical Characterization Of Carbon Fiber/Bucky Paper/Zinc Oxide Hybrid Composites, Suma Ayyagari

Doctoral Dissertations and Master's Theses

The quest for multifunctional carbon fiber reinforced composites (CFRPs) expedited the use of several nano reinforcements such as zinc oxide nanorods (ZnO) and carbon nanotubes (CNTs). Zinc oxide is semi-conductor with good piezoelectric and pyroelectric properties. These properties could be transmitted to CFRPs when a nanophase of ZnO is embedded within CFRPs. In lieu of ZnO nanorods, Bucky paper comprising mat of multiwall-carbon nanotubes (MWCNTs) could be sandwiched in-between laminae to construct a functionally graded composite with elevated electrical and thermal conductivities. In this study, a low temperature ( 90_C) hydrothermal synthesis method was utilized to grow ZnO nanorods on …

Computational Investigation Of The Biomechanics Of Babywearing In Regards To Developmental Dysplasia Of The Hip, Gaurav Girish

Doctoral Dissertations and Master's Theses

Developmental Dysplasia of the Hip (DDH) is a congenital condition where an infant’s hip socket is either loose or otherwise unstable. DDH causes a joint instability where the femoral head is not properly situated inside the acetabulum. Etiology of the condition is in part congenital and developmental, with a difference of DDH prevalence between ethnicities. Incidence of DDH is also in some part dependent on cultural practices and activities of the mother and child. The exact nature of this cultural incidence is not clearly understood. A computational approach is hypothesized to identify the impact of babywearing position on the healthy …

Aviation Propulsive Lithium-Ion Battery Packs State-Of-Charge And State-Of-Health Estimations And Propulsive Battery System Weight Analysis, Jingsi Lilly

Doctoral Dissertations and Master's Theses

Aviation propulsive battery pack research is in high demand with the development of electric and hybrid aircraft. Accurate inflight state-of-charge and state-of-health estimations of aviation battery packs still remain challenging. This thesis puts efforts on estimating the state-of-charge, state-of-health, and remaining energy of a lithium- ion propulsive battery pack with a recursive least squares based adaptive estimator. By reading the system measurements (discharging currents and terminal voltages) with persistent excitation, the proposed estimator can determine the present internal parameters of the battery cells and further interpolate them into state-of-charge, state-of-health, and the remaining energy information. The validation results indicate that …

Aerodynamic And Performance Analysis Of A Morphing Helicopter Rotor System, Vinay Gopal Krishnan

Doctoral Dissertations and Master's Theses

The purpose of this study was to investigate the effect of rotor morphing, specifically variable rotor speed and variable blade twist, on various parameters such as the distribution of angle of attack, lift, power, thrust and/or other metrics describing the performance of a helicopter rotor. A MATLAB based blade element theory model was developed and executed for different flight conditions. The model was validated against the flight test data of a UH-60. Effects on power, lift to drag ratio and rotor drag from variations in blade twist, rotor speed, rotor radius and blade chord was analyzed. Morphing cases were applied …

Design Of Flight Control Laws For A Novel Stratospheric Dual-Aircraft Platform, Cindy Nshuti

Doctoral Dissertations and Master's Theses

Dual-aircraft platform (DAP) is a novel concept that features two glider-like unmanned aerial systems (UAS) tethered via a thin adjustable cable allowing them to sail back-and-forth, without propulsion, using vertical wind shear. DAP offers the potential of a low-cost atmospheric satellite. This thesis presents the results of an initiative to demonstrate this novel flight concept through modeling, simulation, and flight testing at Embry-Riddle Aeronautical University (ERAU). A realistic simulation environment, described herein, was developed to support the development and testing of flight control systems. This environment includes nonlinear aerodynamic models for the aircraft, a multi-element cable dynamics model, propeller-motor thrust …