Aerospace Engineering Commons^™

Analysis And Implementation Of Communications Systems For Small Satellite Missions, Jason S. Harris

Electrical & Computer Engineering Theses & Dissertations

Nano satellites are becoming more and more popular space platforms due to their relatively low cost. Constellations of many of these small satellites are being launched for scientific and research purposes. This thesis has examined implementing a communications system for small satellites that can be used to maintain constant contact with satellites as they orbit the Earth. It analyzes the various components of a small satellite and how they integrate. It then discusses the different abstraction layers that will be required in order to support the same software architecture across various types of hardware. An orbital analysis was performed to …

Simulation Model Of An Automatic Commercial Ice Machine, Haithem Murgham, David Myszka, Vijay Bahel, Rajan Rajendran, Kurt Knapke, Suresh Shivashankar, Kyaw Wynn

Mechanical and Aerospace Engineering Faculty Publications

Automatic commercial ice-making machines that produce a batch of cube ice at regular intervals are known as “cubers." Such machines are commonly used in food service, food preservation, hotel, and health service industries. The machines are typically rated for the weight of ice produced over a 24-hour period at ambient air temperatures of 90°F and water inlet temperature of 70°F.

These cubers typically utilize an air-cooled, vapor-compression cycle to freeze circulating water flowing over an evaporator grid. Once a sufficient amount ice is formed, a valve switches to enable a harvest mode, where the compressor’s discharge gas is routed into …

Flight Control And Hardware Design Of Multi-Rotor Systems, Nathan M. Zimmerman

Master's Theses (2009 -)

This thesis overviews crucial concepts involved in achieving quadcopter flight such as orientation estimation and control system implementation. This thesis also presents researchers with comprehensive hardware and software specifications for a quadcopter system. The primary application for this system would be for research with regards to the implementation of advance control techniques as well as data acquisition. Key constructs of this system include hardware software specifications for a flight controller, the radio system, and the sensorless brushless motor controllers. Firstly, the thesis starts by developing a reference frame and a mathematical model for the quadcotper system. Next, flight orientation estimation …

Detecting And Resolving Air Traffic Conflicts Using A Point Of Closest Approach Method, Marc S. Easton

Mechanical & Aerospace Engineering Theses & Dissertations

A geometrical point of closest approach method is used to solve air traffic conflict detection/resolution problems with a single conflict vehicle that is unaware or unable to aid in resolving the conflict. Nonlinear, three degree of freedom equations of motion for a point-mass vehicle are derived and formulated to allow commanded trajectories to steer the vehicle to a desired location. A dynamic model is developed to propagate the vehicle in three dimensions. A closed-loop model implementing a negative feedback controller using a Proportional-Integral-Derivative control scheme is used to drive the vehicle to match the commanded trajectories. A conflict detection/resolution algorithm …

Carbon Deposition During Oxygen Production Using High Temperature Electrolysis And Mitigation Methods, Timothy Adam Bernadowski

Mechanical & Aerospace Engineering Theses & Dissertations

Carbon dioxide in the Martian atmosphere can be converted to oxygen during high temperature electrolysis for use in life-support and fuel systems on manned missions to the red planet. During electrolysis of carbon dioxide to produce oxygen, carbon can deposit on the electrolysis cell resulting in lower efficiency and possibly cell damage. This would be detrimental, especially when the oxygen product is used as the key element of a space life support system. In this thesis, a theoretical model was developed to predict hazardous carbon deposition conditions under various operating conditions within the Martian atmosphere. The model can be used …

Design Of Experiments Enhanced Statistical Process Control For Wind Tunnel Check Standard Testing, Ben D. Phillips

Mechanical & Aerospace Engineering Theses & Dissertations

The current wind tunnel check standard testing program at NASA Langley Research Center is focused on increasing data quality, uncertainty quantification and overall control and improvement of wind tunnel measurement processes. The statistical process control (SPC) methodology employed in the check standard testing program allows for the tracking of variations in measurements over time as well as an overall assessment of facility health. While the SPC approach can and does provide researchers with valuable information, it has certain limitations in the areas of process improvement and uncertainty quantification. It is thought by utilizing design of experiments methodology in conjunction with …

A Hybrid Tabu/Scatter Search Algorithm For Simulation-Based Optimization Of Multi-Objective Runway Operations Scheduling, Bulent Soykan

Engineering Management & Systems Engineering Theses & Dissertations

As air traffic continues to increase, air traffic flow management is becoming more challenging to effectively and efficiently utilize airport capacity without compromising safety, environmental and economic requirements. Since runways are often the primary limiting factor in airport capacity, runway operations scheduling emerge as an important problem to be solved to alleviate flight delays and air traffic congestion while reducing unnecessary fuel consumption and negative environmental impacts. However, even a moderately sized real-life runway operations scheduling problem tends to be too complex to be solved by analytical methods, where all mathematical models for this problem belong to the complexity class …

A Comparison Of Microstructure And Uniaxial Compressive Response Of Ice-Templated Porous Alumina Scaffolds Fabricated From Two Different Particle Sizes, Nikhil D. Dhavale

Mechanical & Aerospace Engineering Theses & Dissertations

Development of bio-inspired highly porous (>50 vol.%) cellular ceramics is crucial to meet the demand of high-performance lightweight and damage-tolerant materials for a number of cutting-edge applications including impact energy absorption, biomedical implants, and energy storage. A key design feature that is observed in many natural materials (e.g., nacre, bamboo, wood, etc.) is the presence of hierarchical microstructure that results in an excellent synergy of various material properties, which are otherwise considered as mutually exclusive in current paradigm of materials design. To this end, development of multilayered, interconnected and anisotropic cellular ceramics could benefit the aforementioned applications. However, mimicking …

Development And Implementation Of A Propeller Test Capability For Gl-10 "Greased Lightning" Propeller Design, Brian Edward Duvall

Mechanical & Aerospace Engineering Theses & Dissertations

Interest in small unmanned aerial vehicles has increased dramatically in recent years. Hybrid vehicles which allow forward flight as a fixed wing aircraft and a true vertical landing capability have always had applications. Management of the available energy and noise associated with electric propeller propulsion systems presents many challenges. NASA Langley has developed the Greased Lightning 10 (GL-10) vertical takeoff, unmanned aerial vehicle with ten individual motors and propellers. All are used for propulsion during takeoff and contribute to acoustic noise pollution which is an identified nuisance to the surrounding users. A propeller test capability was developed to gain an …

Development Of The Compact Jet Engine Simulator From Concept To Useful Test Rig, Henry H. Haskin

Mechanical & Aerospace Engineering Theses & Dissertations

Two Compact Jet Engine Simulator (CJES) units were designed for integrated wind tunnel acoustic experiments involving a Hybrid Wing Body (HWB) vehicle. To meet the 5.8% scale of the HWB model, Ultra Compact Combustor technology from the Air Force Research Laboratory was used. The CJES units were built and integrated with a control system in the NASA Langley Low Speed Aero acoustic Wind Tunnel. The combustor liners, plug—vane and flow conditioner components were built in-house at Langley Research Center. The operation of the CJES units was mapped and fixes found for combustor instability tones and rig flow noise. The original …

The Effect Of Generation On Retention Of Women Engineers In Aerospace And Industry, Kristine Maria Kiernan

Doctoral Dissertations and Master's Theses

The purpose of this dissertation was to determine the nature and extent of differences between generational cohorts regarding the effect of family factors on retention of women in engineering, with an emphasis on women in the aerospace industry. While 6% of the aerospace workforce is made up of aeronautical engineers, an additional 11.2% of the aerospace workforce is drawn from other engineering disciplines. Therefore, the analysis included all engineering sub-disciplines. In order to include women who had left the workforce, women in all industries were used as a proxy for women in aerospace.

Exits to other fields were modeled separately …

Applying Newton’S Law Of Cooling When The Target Keeps Changing Temperature, Such As In Stratospheric Ballooning Missions, James Flaten, Kaye Smith, Erick Agrimson

2017 Academic High Altitude Conference

Newton’s Law of Cooling describes how a “small” system, such as a thermometer, comes to thermal equilibrium with a “large” system, such as its environment, as a function of time. It is typically applied when the environment is in thermal equilibrium and the conditions are such that the thermal decay time for the thermometer is a constant. Neither of these conditions are met when measuring environmental (i.e. atmospheric) temperature using a thermometer mounted in a payload lofted into the stratosphere under weather balloons. In this situation the thermometer is in motion so it encounters layer after layer of atmosphere which …

Ultra-High Temperature Full Field Deformation Measurements Of Materials Subjected To Thermo-Mechanical Loading: A Dic Based Study, Guillemo A. Valeri Paoli

Theses and Dissertations

Determining the mechanical response of materials at elevated temperatures is a subject of great interest in metal forming, aerospace and aero-engine industries. For example, measurement of the deformation response under tensile loading at high temperatures is crucial for establishing thermomechanical and thermo-physical properties of materials, consequently, determining the reliability of a component or structure exposed to elevated temperatures. In order to predict the behavior of materials at ultra-high temperatures, a novel experimental approach based on Digital Image Correlation (DIC) is proposed and successfully applied to different materials at temperatures ranging from room temperature to 1100˚C. In these studies, a portable …

Design, Manufacturing, And Testing Of A Small Through-Flow Wave For Use Within The Brayton Cycle, Micahel J. Mcclearn

Theses and Dissertations

With the ever growing popularity of drones and other unmanned aerial vehicles for military, commercial, and private usage, there is a desire to improve performance in terms of range, altitude, and flight speed. Current technology uses either electric motors or internal combustion engines: both piston and jet engine types. These sorts of engines undergo significant efficiency degradation as their size decreases. While some efficiency may be recovered via intensive design studies, the cycles are approaching the limit to their operating physics. A possible solution to this is to change the operating physics to something more immune to scaling losses; a …

Design And Experimentation Of A Premixed Rotating Detonation Engine, Ionio Q. Andrus

Theses and Dissertations

Desire for a more efficient air breathing engine has shifted research attention to the Rotating Detonation Engine (RDE). Detonation is a more efficient combustion process than deflagration and provides a pressure gain. The RDE detonation cycle occurs in a compact volume to produce a high specific impulse engine. Computational fluid dynamic (CFD) models have predicted higher specific impulse and detonation wave speeds than has been seen in experimental RDE. The CFD models frequently assume premixed reactants and ignore inlet geometries to facilitate rapid computation. An experimental premixed RDE was sought to test if the premixed assumption in CFD was the …

Meeting The Dod’S Tactical Weather Needs Using Cubesats, Shayna K. Mckenney

Theses and Dissertations

This thesis investigates a CubeSat design that uses Commercial-Off-The-Shelf (COTS) components to capture, store, process, and downlink collected terrestrial weather data at resolutions near stat-of-the-art. The weather phenomena to be detected and transmitted in a timely manner are cloud formations, wind profiles, ocean currents, sea state, lightning, temperature profiles, and precipitation. It is hypothesized and shown that the proposed design will provide an improvement on the current U.S. tactical weather collection satellites because of the anticipated increased reliability and lowered cost to build and maintain the proposed CubeSat constellation. The methodology employed a multi-phase approach through the collective research of …

Test And Verification Of A Cubesat Attitude Determination And Control System In Variable Magnetic Fields, Eric A. Bassett

Theses and Dissertations

The Center for Space Research and Assurance (CSRA) at the Air Force Institute of Technology (AFIT) continues to explore CubeSat initiatives for solving many current space security issues. Regardless of the mission requirements, the success of the Cube- Sat on orbit frequently depends on the Attitude Determination and Control System (ADCS) functioning correctly. Previous research at AFIT has demonstrated single axis control on a spherical air bearing test bed incorporated within a Helmholtz cage utilizing artificially strong magnetic fields for better signal to noise ratios which are not experienced on orbit. This research explores the process of redesigning, testing, and …

Estimation Of Performance Airspeeds For High-Bypass Turbofans Equipped Transport-Category Airplanes, Nihad E. Daidzic

Journal of Aviation Technology and Engineering

Conventional Mach-independent subsonic drag polar does not replicate the real airplane drag characteristics exactly and especially not in the drag-divergence region due to shock-induced transonic wave drag. High-bypass turbofan thrust is a complicated function of many parameters that eludes accurate predictions for the entire operating envelope and must be experimentally verified. Fuel laws are also complicated functions of many parameters which make optimization and economic analysis difficult and uncertain in the conceptual design phase. Nevertheless, mathematical models and predictions have its important place in aircraft development, design, and optimization. In this work, airspeed-dependent turbofan thrust and the new fuel-law model …

Chaotic Advection-Driven Mixing In Unsteady Three-Dimensional Mhd Flows In Microfluidic Devices, Fangping Yuan, Kakkattukuzhy M. Isaac

Collaborative Research: Actively Controllable Microfluidics with Film-Confined Redox-Magnetohydrodynamics -- Video and Data

No abstract provided.

Quantum Computers Are Coming And Will Be Able To Solve Complex Aviation And Aerospace Problems, Nihad E. Daidzic

Aviation Department Publications

No abstract provided.

Predicting Flexural Strength Of Composite Honeycomb Core Sandwich Panels Using Mechanical Models Of Face Sheet Compressive Strength, Nicholas Bruffey, William Shiu

Materials Engineering

The design process at Zodiac Aerospace requires the ability to accurately predict the strength of a composite honeycomb core sandwich panel to adhere to strict FAA regulations. The most common failure mode in long beam composites is in compression. Following ASTM D7249 for a four-point bend test of a long beam flexural test, a mechanical model has been developed that relates the compressive strength of glass fiber face sheets to the flexural strength of the sandwich panel. Zodiac does not currently have data on the compressive strength of the face sheets, so testing was performed to find this property. Asymmetric …

Controlling Grain Size In Cold Worked And Annealed 1100 Aluminum To Optimize Ductility In Rocket Diaphragm Systems, Ryan Lewis, Bryce Simmons, Jessica Williams

Materials Engineering

Liquid propellant rocket diaphragms require extreme ductility. 1100 Aluminum is used for its high ductility, but the post-processing cold work and subsequent anneal result in excessively large grains. The effect of heat treatment and cold work on grain size in 1100 aluminum was explored. The samples were cold worked to 0, 5, 10, 15 and 30% using tensile elongation. The samples were then heat treated per AMS 2770 with either a "Steel Conduction" (1000 – 1150°F/min) or a "Production" (16 – 18°F/min) heating rate. The grain size of the samples were measured using the mean lineal intercept method. The grain …

Subsystem Failure Analysis Within The Horizon Simulation Framework, Ian M. Lunsford

Master's Theses

System design is an inherently expensive and time consuming process. Engineers are constantly tasked to investigate new solutions for various programs. Model-based systems engineering (MBSE) is an up and coming successful method used to reduce the time spent during the design process. By utilizing simulations, model-based systems engineering can verify high-level system requirements quickly and at low cost early in the design process. The Horizon Simulation Framework, or HSF, provides the capability of simulating a system and verifying the system performance. This paper outlines an improvement to the Horizon Simulation Framework by providing information to the user regarding schedule failures …

Flow Meter Test Rig, Cory Davis, Emily Guss, Michael Swartz

Mechanical Engineering

As part of a fluid mechanics laboratory, there should be an experiment that demonstrates the proper use of flow meters, devices that are necessary and relevant in many fluids-related industries. In order to provide students with exposure to these types of devices and how they work, a test rig was developed with the ability to interchange a variety of flow meters in order to broaden the students’ knowledge of the different types of measuring devices. This report was also written to outline the steps taken to ensure the test rig would match a laboratory and industry setting. Additionally, it was …

Tilt-Rotor Drone, Benjamin Stone, Zachary Crandall

Electrical Engineering

A drone is defined a "an unmanned aircraft that can fly autonomously[2]." In the year 2016, there exist many applications for small scale drones. Drones, having had primarily military applications, now have use in hobby robotics, photography, and even in surveying. But drones have not yet been perfected and still have room for much improvement. Several problems with drones come in the form of battery life, stability, and size. Large drones can fit many sensors and probes, but are heavy and have less flight time. For autonomous drones, stability can be an issue even though there exist many stable drones. …

A Study Of Constant Voltage Anemometry Frequency Response, Alex D. Powers

Master's Theses

The development of the constant voltage anemometer (CVA) for the boundary layer data system (BLDS) has been motivated by a need for the explicit autonomous measurement of velocity fluctuations in the boundary layer. The frequency response of a sensor operated by CVA has been studied analytically and experimentally. The thermal lag of the sensor is quantified by a time constant, M_CVA. When the time constant is decreased, the half-amplitude cut-off frequency, f_CVA, is increased, thereby decreasing the amount of attenuation during measurements. In this thesis, three main approaches have been outlined in theory and tested experimentally …

Autonomous Formation Flying And Proximity Operations Using Differential Drag On The Mars Atmosphere, Andres Eduardo Villa

Master's Theses

Due to mass and volume constraints on planetary missions, the development of control techniques that do not require fuel are of big interest. For those planets that have a dense enough atmosphere, aerodynamic drag can play an important role. The use of atmospheric differential drag for formation keeping was first proposed by Carolina L. Leonard in 1986, and has been proven to work in Earth atmosphere by many missions. Moreover, atmospheric drag has been used in the Mars atmosphere as aerobraking technique to decelerate landing vehicles, and to circularize the orbit of the spacecraft. Still, no literature was available related …

Design, Manufacture, Dynamic Testing, And Finite Element Analysis Of A Composite 6u Cubesat, Yanina Soledad Hallak

Master's Theses

CubeSats, specially the 6U standard, is nowadays the tendency where many developers point towards. The upscaling size of the standard and payloads entail the increase of the satellite overall mass. Composite materials have demonstrated the ability to fulfill expectations like reducing structural masses, having been applied to different types of spacecraft, including small satellites.

This Thesis is focused on designing, manufacturing, and dynamic testing of a 6U CubeSat made of carbon fiber, fiberglass, and aluminum.

The main objective of this study was obtaining a mass reduction of a 6U CubeSat structure, maintaining the stiffness and strength. Considering the thermal effects …

Sysml Based Cubesat Model Design And Integration With The Horizon Simulation Framework, Shaun Luther

Master's Theses

This thesis examines the feasibility of substituting the system input script of Cal Poly’s Horizon Simulation Framework (HSF) with a Model Based Systems Engineering (MBSE) model designed with the Systems Modeling Language (SysML). A concurrent student project, SysML Output Interface Creation for the Horizon Simulation Framework, focused on design of the HSF Translator Plugin which converts SysML models to an HSF specific XML format. A SysML model of the HSF test case, Aeolus, was designed. The original Aeolus HSF input script and the translated SysML input script retained the format and dependency structure required by HSF. Both input scripts …

An Iteration On The Horizon Simulation Framework To Include .Net And Python Scripting, Morgan Yost

Master's Theses

Modeling and Simulation is a crucial element of the aerospace engineering design pro- cess because it allows designers to thoroughly test their solution before investing in the resources to create it. The Horizon Simulation Framework (HSF) v3.0 is an aerospace modeling and simulation tool that allows the user to verify system level requirements in the early phases of the design process. A low fidelity model of the system that is created by the user is exhaustively tested within the built-in Day-in-the-Life simulator to provide useful information in the form of failed requirements, system bottle necks and leverage points, and potential …