Aerospace Engineering Commons^™

Development Of A Self-Orienting Cubesat Solar Array, Eric Mcgill

Honors Theses

The sponsor of this conceptual design project was the Air Force Institute of Technology (AFIT) at WrightPatterson Air Force Base in Dayton, Ohio. AFIT was striving to give CubeSats more capability to conduct research, reconnaissance, and other functions. One of the major barriers for AFIT to overcome to give CubeSats more capability was the ability of the CubeSat to generate usable power while in orbit. All of AFIT’s CubeSats generated the power needed while in orbit with solar panels that are rigidly mounted to the outside of the craft. AFIT believes that a new design for the solar array used …

Single Axis Stability Autonomous Glider Control, Brian Study

Student Works

To investigate and increase knowledge on autonomous control systems, an autonomous glider was fitted with a control system with the purpose of creating a craft that would be capable of maintaining a wings level condition despite perturbations to the trim condition. The glider measures bank angle and roll rate information from an accelerometer and gyro, before it relays the data to an equipped microcontroller. Programmed on the microcontroller is a control law to take the input from the sensors and issue a command to a single servo that controls both ailerons, allowing for the vehicle to autonomously correct its bank …

Direct Metal Laser-Sintered Stainless Steel: Comparison Of Microstructure And Hardness Between Different Planes, M. Ghasri-Khouzani, H. Peng, R. Attardo, P. Ostiguy, J. Neidig, R. Billo, D. Hoelzle, M. R. Shankar

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Microstructural analysis and micro-hardness measurements were performed on different planes of 316L stainless steel fabricated by direct metal laser sintering (DMLS) technique. A fine cellular network was observed within the steel microstructure, where morphology of most cells changed from columnar on XZ-plane (vertical section) to equiaxed on XY-plane (horizontal section). Correspondingly, morphology of most grains was found to alter from columnar for the XZ-plane to equiaxed in the case of the XY-plane. Moreover, X-ray diffraction (XRD) analysis revealed a fully austenitic structure for both the planes. The average micro-hardness value for the XZ-plane and XY-plane was insignificantly (≈ 3%) different, …

A Study Of Flight Simulation Training Time, Aircraft Training Time, And Pilot Competence As Measured By The Naval Standard Score, Aaron D. Judy

Doctor of Education (Ed.D)

The purpose of the study was to investigate the relationships between US Navy T-45C flight simulation training time, actual aircraft training time, and intermediate and advanced jet pilot competence as measured by the Naval Standard Score (NSS). Examining the relationships between US Navy T-45C flight simulation time and actual aircraft flight time may provide further information on flight simulation training versus actual aircraft training to aviation authorities, flight instructors, the military aviation community, the commercial aviation community, and academia. The study was non-experimental, correlational, causal-comparative with an emphasis upon the establishment of mathematic and predictive relationships using archival data from …

Influence Of Reverse Shoulder Implant Positioning On Patient-Specific Muscle Forces: A Simulation Study, Kayla Marie Pariser

Honors Theses

A reverse total shoulder arthroplasty (RTSA) is a common treatment used to stabilize the shoulder and improve range of motion in patients with torn rotator cuff muscles. Shoulder stability relies on the shoulder muscles. With rotator cuff tears, the RTSA enables the deltoid muscle to become the primary stabilizer of the shoulder joint. To improve stability, RTSAs increase the deltoid muscle moment arm and decrease the required torque about the shoulder joint for movement. Currently, there is not standardized, objective method for a surgeon to position an implant on a specific patient. This study is part of a larger, ongoing …

Numerical And Analytical Modelling For Droplet Evaporation Resulting In Convective Flow Cooling Verified By Experimentation, Adwaith Ravichandran

Theses and Dissertations

The temperature of a gaseous convective stream can be reduced by injecting a colder liquid into the stream. The extent to which this gas temperature can be reduced depends on the amount of liquid being injected into the gas flow domain, rate of energy transfer (heat) from the gas phase to the liquid resulting in evaporation and the length of the domain itself referred to in this study as a “mixer”. This study proposes the use of a non-dimensional Damkohler number that relates the liquid residence time and the liquid life time which could serve as a yardstick to determine …

Design And Implementation Of An Artificial Neural Network Controller For Quadrotor Flight In Confined Environment, Ahmed Mekky

Mechanical & Aerospace Engineering Theses & Dissertations

Quadrotors offer practical solutions for many applications, such as emergency rescue, surveillance, military operations, videography and many more. For this reason, they have recently attracted the attention of research and industry. Even though they have been intensively studied, quadrotors still suffer from some challenges that limit their use, such as trajectory measurement, attitude estimation, obstacle avoidance, safety precautions, and land cybersecurity. One major problem is flying in a confined environment, such as closed buildings and tunnels, where the aerodynamics around the quadrotor are affected by close proximity objects, which result in tracking performance deterioration, and sometimes instability. To address this …

Volterra Series Approximation For Multi-Degree Of Freedom, Multi-Input, Multi-Output, Aircraft Dynamics, Alexander J. Chen

Mechanical & Aerospace Engineering Theses & Dissertations

An analytical model of a second order system is extended from a single-axis framework, to a multi-axis, multi-degree of freedom framework for a multiple input, multiple output system. This mathematical model is built from the variational approach of the Volterra series representation of nonlinear systems. The new representation describes the second order, oscillatory natural modes of a system, and shows how to organize the Volterra terms in intuitive ways. The constructed mathematical model aims to establish an organization of the Volterra kernels to allow for analytical cause and effect type analysis on system behavior.

To demonstrate the accuracy of the …

A Cost Effective Design For A Propeller Thrust/Torque Balance, Nicholas Barrett Sadowski

Mechanical & Aerospace Engineering Theses & Dissertations

Wind tunnel balances are used with aircraft models, propellers, and components to measure applied forces and moments. The design and manufacture of a balance is often for a specific test, test article and conditions. This paper discusses the theory, design, calibration, and testing of a new small propeller balance for use in a low-speed wind tunnel. The new balance is named the ODU15X15.

Theory discussed herein covers how the two measurement components, thrust and torque, affect the balance design. These loads generate strains which are in turn read by strain gages arranged in Wheatstone bridges. The design follows well known …

Determination Of Chemical Notch, KChem On Aluminum And Steel When Subjected Under Slow Strain Rate Test In Corrosive Environment, Joshua Teo Lee Kuok

Masters Theses

When designing for any mechanical components or system, the question would arise as to how the material would react to the loads subjected on it? Would the component survive its service load? How would it react to environmental corrosion? To answer these questions, the technique used in this thesis paper is the Slow Strain Rate Test (SSRT) method. Aluminum and steel were chosen as the material to be tested in this paper. Al 7075-T651, and Al 6061-T651 was chosen due to its wide range of application, high strength to weight ratio and ease of machinability. It is highly used in …

Sysml Output Interface And System-Level Requirement Analyzer For The Horizon Simulation Framework, Viren Kishor Patel

Master's Theses

Model-Based Systems Engineering in industry has been constantly increasing its presence within the aerospace industry. SysML is one such MBSE tool that shows complex system organization and relationships. The Horizon Simulation Framework is another MBSE tool, created by Cal Poly students, that gives users the ability to run “day-in-the-life” simulations of systems. Finding a way to link these two tools could allow systems engineers to reap the benefits of both.

This thesis investigates the background and design process involved with developing the code that can convert an output file generated in SysML, into a format specifically made for the Horizon …

Safety Analysis Of Automatic Dependent Surveillance – Broadcast (Ads-B) System, Rajee Olaganathan

Publications

ADS-B is one of the significant implementation systems of NextGen, to help pilots and air traffic controllers to create a safer, and more efficient National Airspace System (NAS). First, this research paper will briefly describe the ADS-B system, its design structure, ADS-B In and ADS-B Out systems, its efficiency both in pilot applications and in air traffic control applications, and then discuss about the system safety analysis. The preliminary hazard analysis and fault tree analysis will be done for the identified and selected hazards, and will be briefly discussed. The paper will conclude by providing recommendations to prevent/mitigate the hazards …

Numerical Analysis Of A Compact Helical Counterflow Heat Exchanger, Manikandan Chidambaram

Theses and Dissertations

The performance of compact counter flow heat exchangers with helically shaped passages is examined using a 1-D analytical model and compared with a high-fidelity 3-D numerical simulation. The 1-D model is capable of assessing the general trends associated with the heat transfer performance and fluid pressure losses, whereas the high fidelity 3-D numerical model is needed to provide more accuracy. For water flow rates of 0.01 kg/s -1 kg/s, the models are used to predict the overall heat transfer coefficient ratio for a straight and counter helix heat exchanger. The maximum difference between the 3-D numerical and 1-D analytical model …

Case Study: Cooling Channels For Material Testing Applications Using Laser Powder Bed Fusion, Benjamin M. Doane, Ryan P. O'Hara, K. Liu, Carl R. Hartsfield

Faculty Publications

Additive Manufacturing continues to gain a reputation as a key technology that will have a major impact on all aspects of mechanical engineering. The United States Air Force’s (USAF) Air Force Institute of Technology (AFIT), based in Dayton, Ohio, has expanded its AM-focused education and R&D capabilities with the purchase of a Laser Powder Bed Fusion system from Germany’s Concept Laser.

Distributed Sensing And System Identification Of Cantilever Beams And Plates In The Presence Of Weak Nonlinearities, Patrick Sean Heaney

Mechanical & Aerospace Engineering Theses & Dissertations

While the mathematical foundation for modal analysis of continuous systems has long been established, flexible structures have become increasingly widespread and developing tools for understanding their mechanics has become increasingly important. Cantilever beams and plates, in particular, have been extensively studied due to their practical importance as approximations of more complex structures. The focus of this thesis is on understanding the dynamics of vibrating cantilever beams and plates through analytical and experimental investigation. Various models for the mechanics of these structures, of varying physical fidelity, are described and compared. A fiber optic sensing system is utilized to experimentally acquire distributed …

Learn-To-Fly Control System Design, Alexander Brent Streit

Electrical & Computer Engineering Theses & Dissertations

In order to improve aircraft flight control system development life cycle, new flight control techniques are being explored to allow the system to ``learn-to-fly" with limited a priori information of the aircraft's aerodynamic characteristics. One approach is to have a system identification process operating on-the-fly to generate mathematical models which can be used to update control laws. In this thesis, a wind tunnel experiment was conducted with a model aircraft set up to be free-to-roll, so system identification and control methods could be explored for a one-degree-of-freedom case. In particular this thesis covers the design of a novel control system …

Development Of A Static Aeroelastic Database Using Nastran Sol 144 For Aircraft Flight Loads Analysis From Conceptual Design Through Flight Test, Ryan M. Haughey

Theses and Dissertations

This paper describes a method for predicting aircraft aerodynamic and inertial loading on a structural finite element model, (FEM) based on static aeroelastic coefficients. These coefficients are computed via interpolated spline methods within NASTRAN Solution 144 (static aeroelastic solution) and the “TRIM” module to connect the doublet-lattice model (DLM) and the structural finite element model for a coupled solution. The database is created by selecting key breakpoints where linear interpolation techniques can be utilized to develop and predict static aeroelastic coefficients for the prediction of any aircraft state for a given transient solution. This method is applicable from conceptual design …

Evaluation Of Augmented Reality Glasses For Use In Flight Test Courses, Leonardo Macena Silveira

Theses and Dissertations

The objective of this thesis research was to analyze the implementation of new technologies into the flight test engineering major courses at Florida Institute of Technology. The focus was to use current augmented reality technology available in the market and create ways the students would be able to use it while performing experiments. Augmented reality is not the same as virtual reality. It is a technology that generates computer images of effect into an existing reality. In easier words, augmented reality projects images into the real-life surroundings the user locates. It allows the user to interact with the computer while …

Experimental Investigation Of A New Spiral Wingtip, Naseeb Ahmed Siddiqui, Mohammed Aldheeb, Waqar Asrar, Erwin Sulaeman

International Journal of Aviation, Aeronautics, and Aerospace

Experiments on the relative merits and demerits of slotted wingtips mimicking a bird’s primary feathers have been performed. The real emargination length of feather tips, their flexibility and curved shapes during cruise are considered in the present study. The experiments were performed at a Reynolds number of 3.7 x 10⁵ on a symmetric flat plate half wing of aspect ratio 3. Lift, drag and pitching moments were measured using a six component aerodynamic balance. Four different shapes inspired by bird primary feathers have been analysed. The rigid curved tip performed the best increasing the L/D ratio by 20%. This …

Nanosatellite Space Experiment, Robert J. Twiggs

Robert "Bob" Twiggs STEM Education Collection

A report written by Professor Bob Twiggs titled "Nanosatellite Space Experiment" from March 30, 2018.