Aerospace Engineering Commons^™

Disc Golf Throwing Robot, Nevada S. Schultz, Sydney M. Lewis, Erick Edmundo Daza, Rachel Alysse Greenberg, Peter M. Kean

Mechanical Engineering

Disc golf companies need better methods to test disc flight. The scope of this project is to create a disc throwing robot that can throw a disc golf driver 450-500 feet, with control over the speed, spin, and release angle. Research shows that multiple disc-throwing products exist; however, none meet the full requirements of this project. The Cal Poly senior project design team created a proof-of-concept machine. This prototype started as a two-wheel mechanism. Eventually, a third wheel was added, allowing for complete control over disc spin. The three-wheel prototype reached 62 mph when perfectly calibrated. The prototype is accurate, …

Distributed Control Of Servicing Satellite Fleet Using Horizon Simulation Framework, Scott Plantenga

Master's Theses

On-orbit satellite servicing is critical to maximizing space utilization and sustainability and is of growing interest for commercial, civil, and defense applications. Reliance on astronauts or anchored robotic arms for the servicing of next-generation large, complex space structures operating beyond Low Earth Orbit is impractical. Substantial literature has investigated the mission design and analysis of robotic servicing missions that utilize a single servicing satellite to approach and service a single target satellite. This motivates the present research to investigate a fleet of servicing satellites performing several operations for a large, central space structure.

This research leverages a distributed control approach, …

Coupled Boundary Conditions For Modeling Airbreathing Engines, Adam Louis Waldemarson

Master's Theses

Modeling the flight conditions of an aircraft that utilizes an airbreathing propulsion system necessitates a method to account for the increase in energy introduced into the flow. Current methods for modeling engines either assign fixed conditions on flat faces on the intake and exhaust through a manual process with the use of external models or attempt to model the flow through the engine within the simulation using complex and computationally expensive geometry and solvers. The method presented attempts to provide an intermediate option to model airbreathing engines through coupling the intake and exhaust boundary conditions with a parametric engine model. …

Refactoring Dependency Loading And Standardizing Factory Patterns In The Horizon Simulation Framework, Jack W. Kelly

Master's Theses

The Horizon Simulation Framework (HSF) is an open-source community driven mod- eling and simulation tool developed over 15 years by a lineage of Cal Poly graduate students. The tool excels in its flexibility to model an assortment of complex systems, with prebuilt modeling elements available for the simulation of space missions. A high-level simulation tool like HSF lends itself to an agile development cycle as system constraints can be quickly identified through day in the life simulation of the modeled system. The objective of the work presented in this thesis is to refactor the way in which several modeling elements …

Solving Supersonic Flows Using The Method Of Integral Relations In Python, Eddie Hsieh

Master's Theses

This thesis presents a modern approach to the Method of Integral Relations implemented in the Python programming language. This work is based on South's reports on solving supersonic conical flows and Belotserkovskii's publications on solving supersonic flows over blunt bodies. The Python SciPy library is extensively used in this thesis. A root finder module is used to perform South's solution process, and the Runge-Kutta ODE solver with dense output is implemented to replicate Belotserkovskii's solution process. The implementation of Python makes the development efficient and serves as an open-source framework for future work to build on. This work focuses on …

Composite Solid Rocket Motor Case Optimization With Matlab Genetic Algorithm, Aleksandr Breit

Master's Theses

This study utilizes MATLAB genetic algorithm (GA) to perform optimization on a solid rocket motor (SRM) chamber structure. The (SRM) structure is modelled as a cylindrical composite laminate where unidirectional fiber orientations are the primary design variable in the optimization problem formulation. Additional design variables such as chamber length, diameter, and internal pressure are altered along with the ply angles to minimize the safety margin towards a near-zero value and encourage efficient layup design. Classical lamination theory with Tsai-Wu failure criterion are used to calculate ply-level safety margins. A thickness minimization scheme is employed to reduce the ply count from …

Feasibility Assessment Of An All-Electric, Narrow-Body Airliner, Ariel Sampson

Master's Theses

Combustion emissions from aviation operations contribute significantly to climate change and air pollution. Accordingly, there is increasing interest in advancing battery-powered propulsion for aviation applications to reduce emissions. As batteries continue to improve, it is essential to recognize breakthroughs in battery specific energy in the context of air transport vehicles. Most electric aircraft designs and programs have focused on small aircraft because of restrictive battery performance. This work presents a feasibility assessment for an all-electric airliner based on an Airbus A220-100 with turbofan engines replaced by electric motors and propellers. The analysis compares the performance characteristics of the electric airliner …

Development Of Mirror Flexures For Use In The Muvi Instrument, Colin W. Harrop

Master's Theses

The Miniaturized Ultraviolet Imager (MUVI), is a compact wide field UV imaging instrument in development at UC Berkeley Space Sciences Laboratory and Cal Poly, San Luis Obispo. MUVI is designed to fit in a 2U CubeSat form factor and provide wide field, high resolution images of the ionosphere at far ultraviolet wavelengths. This thesis details the design and analyses of MUVI’s deployable cover mirror mounting flexures. Three different flexure geometries were evaluated, an optimal candidate was determined based on a number of criteria including isolation of vibration and stress to the mirrors, manufacturability and cost. The design of the flexure …

Project Management And Systems Engineering Framework For Educational Cubesat Missions, Bailey Garrett

Master's Theses

The rising complexity of CubeSat missions and the unique challenges faced by educational CubeSat programs lead to high rates of mission failure. Implementing project management and systems engineering practices can alleviate these challenges and improve mission success rates for educational CubeSat developers. However, existing project management and systems engineering resources are too cumbersome and often assume the student has a base-level understanding of project management and systems engineering fundamentals. A new universal project management and systems engineering framework was created and tailored specifically to the needs of an educational CubeSat mission. The framework was designed to accommodate first-time CubeSat developers, …

Effects Of Atomic Oxygen On Outgassing Of Silicone Materials, Samuel Westrick

Master's Theses

An important consideration for spacecraft material selection is the space environment that the spacecraft will be operating in. Two features of the space environment that drive material selection are material outgassing and the presence of atomic oxygen in low Earth orbit (LEO). Materials that are considered for use in space are tested to be able to understand how they’ll outgas on orbit and how they’ll respond to interactions with atomic oxygen. However, testing to understand how atomic oxygen interaction with a material will affect how the material will outgas is rare and not standardized. This thesis used a vacuum chamber …

Testing And Verification For The Open Source Release Of The Horizon Simulation Framewortesting And Verification For The Open Source Release Of The Horizon Simulation Framework, William J. Balfour

Master's Theses

Modeling and simulation tools are exceptionally useful for designing aerospace systems because they allow engineers to test and iterate designs before committing the massive resources required for system realization. The Horizon Simulation Framework (HSF) is a time-driven modeling and simulation tool which attempts to optimize how a modeled system could perform a mission profile. After 15 years of development, the HSF team aims to achieve a wider user and developer base by releasing the software open source. To ensure a successful release, the software required extensive testing, and the main scheduling algorithm required protections against new code breaking old functionality. …

A Study Of Pressure Probe Response In Steady And Unsteady Flows, Michael T. Charonnat

Master's Theses

The objective of this thesis is two-fold: to analyze the directional calibration of a 3-hole probe in steady flow and to develop a method for the interpretation of measurements recorded with a novel, fast-response Pitot-type probe in unsteady, turbulent flow. Calibration data for the 3-hole probe’s two side ports was taken in the steady, non-turbulent region of a free jet and was evaluated for symmetry. In addition, data that was recorded using one side port in two independent calibration runs was compared to study repeatability. Misalignment was found between the nominally symmetric data sets, which may be the result of …

Development Of A Dual-Band Radio Repeater To Be Carried By A Fixed-Wing Small Unmanned Aerial System, Carl Recine

Master's Theses

With the continued rise in wildfires in California, and around the world, technological advancements are needed to improve the safety and effectiveness of wildland firefighters. One area that provides an opportunity for such development is the deployment of temporary communications networks. Currently, radio repeaters are set up on mountain tops in the response area; such repeaters do not provide flexibility once installed, still have blind spots, and require the time of valuable assets like helicopters to install.

This thesis will establish the feasibility of airborne radio repeaters for wildland firefighting. In order to successfully demonstrate the feasibility of such an …

Structural Loads And Preliminary Structural Design For A World Speed Record-Breaking Turbo-Prop Racing Airplane, Matthew G. Slymen

Master's Theses

The Cal Poly SLO Turbo-Prop Racer project aims to design a world speed record-breaking aircraft, capable of flying more than 550 miles per hour on a 3-kilometer closed course. To further this endeavor, this thesis presents the calculations of load distributions across the aircraft’s wing and tail and preliminary structural estimates of primary structural components for verification of the loads calculations and for use in a future finite element model. The aircraft’s fundamental design characteristics effect on the structure of the aircraft, namely the unique Y-tail design, are first examined. Then, loads are calculated in accordance with the regulation dictated …

Spacecraft Trajectory Optimization Suite: Fly-Bys With Impulsive Thrust Engines (Stops-Flite), Aaron H. Li

Master's Theses

Spacecraft trajectory optimization is a near-infinite problem space with a wide variety of models and optimizers. As trajectory complexity increases, so too must the capabilities of modern optimizers. Common objective cost functions for these optimizers include the propellant utilized by the spacecraft and the time the spacecraft spends in flight. One effective method of minimizing these costs is the utilization of one or multiple gravity assists. Due to the phenomenon known as the Oberth effect, fuel burned at a high velocity results in a larger change in orbital energy than fuel burned at a low velocity. Since a spacecraft is …

The Effects Of Atomic Oxygen On Silicone And Carbon-Based Contamination, Mayana W. Gordon

Master's Theses

Understanding the space environment and contamination concerns of a spacecraft is critical in designing a successful mission. The ability for a spacecraft to meet its science objectives relies on systems functioning as intended. A concern for maintain- ing performance while on orbit is molecular contamination. Silicones have previously been shown to form a silica layer on their surfaces when exposed to atomic oxygen. For silicone contamination, this translates to a silica film on the contaminated surface. Missions such as Long Duration Exposure Facility and Evaluation of Oxygen Interactions with Materials III have indicated that the silica film can trap deposits …

Uv Space Imager Enclosure Coating, David Silva Cortez, Victor Alexander Rempel Dekhtyar, Maria L. Muñoz

Mechanical Engineering

The goal of this project is to reduce the amount of stray light entering an ultraviolet (UV) imager through absorption. This report outlines the use of ZnO nanoparticles mixed in an epoxy matrix for use in a CubeSat enclosure. Through testing, our team verified that the ZnO and epoxy coating experienced a peak absorption between 360-370 nm. The epoxy mixture with the .75% by weight ZnO nanoparticles absorbed up to 99.9 % of UV light at its peak. The effect on material properties, such as Young’s modulus and ultimate tensile strength, was also tested. Tensile tests demonstrated that adding ZnO …

Method And Simulation Of On-Orbit Sub-Microthrust Evaluation, Jonathan Hood

Master's Theses

With the advent of smaller satellites, along with the need for less than 0.1 μN precision attitude control for interferometry and imaging missions, finer micro- to sub-micro- thrusters have become an area of high interest. As thrusters are developed and ground-tested, it is necessary to evaluate their thrust performance on-orbit. On-orbit measurements offer actual thrust performance in mission conditions, free from ground facility vibrations and miniaturization restraints, and allow a thruster system to achieve a NASA Technology Readiness Level (TRL) of 7-8. A review is conducted of existing and proposed ground and on-orbit thrust measurement techniques. Experimental gaps and complementary …

Low-Cost Uav Swarm For Real-Time Object Detection Applications, Joel Valdovinos Miranda

Master's Theses

With unmanned aerial vehicles (UAVs), also known as drones, becoming readily available and affordable, applications for these devices have grown immensely. One type of application is the use of drones to fly over large areas and detect desired entities. For example, a swarm of drones could detect marine creatures near the surface of the ocean and provide users the location and type of animal found. However, even with the reduction in cost of drone technology, such applications result costly due to the use of custom hardware with built-in advanced capabilities. Therefore, the focus of this thesis is to compile an …

Aeroelastic Analysis Of Small-Scale Aircraft, Kent Roberts

Master's Theses

The structural design of flight vehicles is a balancing act between maximizing loading capability while minimizing weight. An engineer must consider not only the classical static structural yielding failure of a vehicle, but a variety of ways in which structural deformations can in turn, affect the loading conditions driving those deformations. Lift redistribution, divergence, and flutter are exactly such dynamic aeroelastic phenomena that must be properly characterized during the design of a vehicle; to do otherwise is to risk catastrophe. Relevant within the university context is the design of small-scale aircraft for student projects and of particular consideration, the DBF …

Characterization, Design, And Optimization Of Dual-Purpose Wind Turbines And Frost Protection Fans, Ethan Narad

Master's Theses

This thesis report outlines the creation of a MATLAB tool to design reversible machines that can function as both wind turbines and as agricultural frost protection fans. Frost protection fans are used to prevent crop loss during radiative freeze events during which a temperature inversion is present. Such a dual-purpose machine fundamentally has the constraint that it must use symmetric airfoils, so a suite of tools for automatically designing an optimized wind turbine blade with symmetric airfoils using the Blade Element Momentum (BEM) theory approach is presented. The BEM code is then re-derived and adapted for use with a frost …

Developing A Light Curve Simulation Tool For Ground And Space-Based Observations Of Spacecraft And Debris, Andrew T. Ochoa

Master's Theses

A light curve is a plot of brightness versus time of an object. Light curves are dependent on orbit, attitude, surface area, size, and shape of the observed object. Using light curve data, several analysis methods have been developed to derive these parameters. These parameters can be used for tracking orbital debris, monitoring satellite health, and determining the mission of an unknown spacecraft.

This paper discusses the development, verification, and utilization of a tool that simulates light curve data. This tool models ground-based observations, space-based observations, self-shadowing geometry, tumbling debris, and controlled spacecraft. The main output from the tool is …

Break The Ice Challenge, Peter Karkos, Alex Lewis, Eva Kouyate, Vy Han

Mechanical Engineering

The report documents and justifies team LEGION’s senior design project, from research and ideation to prototype manufacturing and testing. It begins by providing some background on the project and outlining the mission scenario given by NASA. This is followed by related literature on excavation of icy regolith on the moon, water transportation, lunar environment, and space law. Next, research is performed into existing products, such as patents and various designs from previous related NASA competitions.

After providing the relevant background information, focused objectives are outlined, with a problem statement, boundary sketch, and engineering specifications. The wants & needs of NASA …

On The Mobility Of Small Aperture Telescopes For Initial Orbit Determination And Apparent Magnitude Derivation Of Low Earth Satellites, Jonathan Ian Hernandez

Master's Theses

Maintaining Space Domain Awareness (SDA) of satellites in low Earth orbit (LEO) requires effective methods of tracking and characterization. Optical measurements of these objects are generally sparse due to limited access intervals and high angular rates. Light pollution and geographic obstructions may also preclude consistent observations. However, a mobile small aperture telescope grants the ability to minimize such environmental effects, thereby increasing capture likelihoods for objects within this regime. By enhancing LEO satellite visibility in this way, extensive orbital and visual data are obtainable.

An 8-inch Meade LX200GPS telescope equipped with a Lumenera SKYnyx2-0M CCD camera comprises the system that …

Optimization Of Interplanetary Transfer Trajectories Using The Invariant Manifolds Of Halo Orbits, Ryan Yedinak

Master's Theses

Traditionally, two-body dynamics have been used to design orbital trajectories for interplanetary missions using a series of Lambert’s transfers and gravity assists. Although these are reliable methods, they have extremely high fuel requirements, especially for missions to outer planets. From an orbital mechanics perspective, three ways of reducing fuel requirements for these types of missions are utilizing low energy transfer trajectories, applying low thrust engine parameters, and implementing orbit optimization techniques.

The goal of this thesis is to combine low energy transfers created from the dynamics of the Circular Restricted Three-Body Problem (CRTBP) with low-thrust orbit optimization techniques to develop …

Interior Point Optimization Of Low-Thrust Spacecraft Trajectories, Jordan D. Frederiksen

Master's Theses

Low-thrust interplanetary spacecraft trajectory optimization poses a uniquely difficult problem to solve because of the inherent nonlinearities of the dynamics and constraints as well as the large size of the search space of possible solutions. Tools currently exist that optimize low-thrust interplanetary trajectories, but these tools are rarely openly available to the public, and when they are available they require multiple interfaces between multiple different packages. The goal of this work is to present a new piece of low-thrust interplanetary spacecraft trajectory optimization software that is open-source and entirely self-contained so that more people can have access to the ability …

Integral Boundary Layer Methods In Python, Malachi Joseph Edland

Master's Theses

This thesis presents a modern approach to two Integral Boundary Layer methods implemented in the Python programming language. This work is based on two 2D boundary layer methods: Thwaites' method for laminar boundary layer flows and Head's method for turbulent boundary layer flows. Several novel enhancements improve the quality and usability of the results. These improvements include: a common ordinary differential equation (ODE) integration framework that generalizes computational implementations of Integral Boundary Layer methods; the use of a dense output Runge-Kutta ODE solver that allows for querying of simulation results at any point with accuracy to the same order as …

Nasa Micro-G Next Challenge: Sample Container Dispensing Device, Kristin G. Kraybill-Voth, Kelsey L. Mickelson, Oscar D. Popravka

Mechanical Engineering

This Final Design Review (FDR) report outlines a Cal Poly San Luis Obispo senior design project developing a sample container dispensing device for NASA Johnson Space Center’s Micro-g NExT design challenge, a competition for university students. NASA aims to bring the first woman and next man to the moon through the Artemis missions beginning in 2024. The Micro-g NExT 2021 challenges focus on developing equipment which will support the Artemis mission, where Astronauts will conduct extensive geological sampling to further the scientific understanding of the moon. Our team designed, built, and tested a device that holds sample bags as they …

Analytical, Numerical, And Computational Methods To Analyze The Time To Empty Open, Closed, And Variable-Topped Inverted Bottles, Callen Schwefler

Master's Theses

Recent unexpected experimental observations of the emptying of inverted bottles with perforations has generated interest in modeling and simulation of this phenomenon. It was observed that as a perforation, i.e., a small hole at the "top" of the inverted bottle, is added and enlarged, the overall emptying time first increases to a maximum value and then decreases until it reaches a lower limit. The change in emptying time is associated with a transition from jetting, where only water exits the neck, to glugging, a competition between air and water flows at the neck of the bottle.

This paper develops analytical …

A Flat Plate Skin Friction Correlation Including Transition, Jaret M. Wedow

Master's Theses

Many existing boundary layer models treat transition as a rapid switch from laminar to turbulent flow, with correlations defining properties in each respective region. Natural transition, however, is not always a very spanwise uniform process, with the onset of transition varying somewhat between different streamwise paths of fluid flow. Thus, a spanwise average of natural transition can result in a more gradual, extended transition region than many existing models predict. Modern applications, such as aircraft wings and fuselages, are extremely streamlined and smooth, allowing for natural transition to occur rather than flow tripping to turbulent near the leading edge. Under …