Aerospace Engineering Commons^™

Thermal Analysis Of A Monopropellant Micropropulsion System For A Cubesat, Erin C. Stearns

Master's Theses

Propulsive capabilities on a CubeSat are the next step in advancement in the Aerospace Industry. This is no longer a quest that is being sought by just university programs, but a challenge that is being taken on by all of the industry due to the low-cost missions that can be accomplished. At this time, all of the proposed micro-thruster systems still require some form of development or testing before being flight-ready. Stellar Exploration, Inc. is developing a monopropellant micropropulsion system designed specifically for CubeSat application.

The addition of a thruster to a CubeSat would expand the possibilities of what CubeSat …

Microphone-Based Pressure Diagnostics For Boundary Layer Transition, Spencer Everett Lillywhite

Master's Theses

An experimental investigation of the use low-cost microphones for unsteady total pressure measurement to detect transition from laminar to turbulent boundary layer flow has been conducted. Two small electret condenser microphones, the Knowles FG-23629 and the FG-23742, were used to measure the pressure fluctuations and considered for possible integration with an autonomous boundary layer measurement system. Procedures to determine the microphones’ maximum sound pressure levels and frequency response using an acoustic source provided by a speaker and a reference microphone. These studies showed that both microphones possess a very flat frequency response and that the max SPL of the FG-23629 …

Creating Exact Bezier Representations Of Cst Shapes, David D. Marshall

Aerospace Engineering

The paper presents a method of expressing CST shapes pioneered by Kulfan into standard Bezier curves and surfaces. Out of the seven standard shape classes identified by Kulfan as representable using CST curves, four of them, including airfoils, can be represented as Bezier curves exactly. For the other three, a convergent series expansion proves insufficient to achieve any practical accuracy, however these three classes are not the most commonly used of the CST classes. With the ability to express most common CST curves and surfaces as generic Bezier curves and surfaces, CST shapes can be used in CAD, solid modeling, …

Control System Infrastructure For The Cal Poly Human Powered Helicopter: Upturn Ii, Douglas A. Thornber, Samuel J. Wahyou

Aerospace Engineering

The Upturn was donated to Cal Poly in October 2012 by Neal Saiki from NTS. Our project was to replicate the old system to decrease the turn-around time in case of a crash during a test flight. The control system for the Upturn II was designed with the same considerations that were used for the Upturn. The result we got was inconclusive for the sensor selection, the new control system is heavier than the old system, and we couldn’t validate the system without doing a flight test. For the next iteration if some of the replication requirements are relaxed the …

Ramjet Combustion Chamber, Paul Cameron Stone

Aerospace Engineering

A ramjet combustion chamber is designed and some initial assembly fabrication and test completed as a component of a ramjet graduate project for California Polytechnic State University, San Luis Obispo Supersonic Wind Tunnel. The combustor design is driven by a theoretical model created by a Cal Poly graduate student, Harrison Sykes. Temperature, pressure, and fuel flow will be measured.

The Effects Of Fabrication Methods And Cure Cycle On The Mechanical Properties Of Carbon Fiber Laminate In Tensile And 3-Point Bend Testing, Adriano Agostino

Aerospace Engineering

This project was completed at the California Polytechnic State University, San Luis Obispo Aerospace Engineering Structures and Composites Lab during Spring Quarter 2013. The purpose of this project was to research and to gain insight into the effects of fabrication methods and of modifying cure cycles for Newport NB-301 12l 2x2 Twill Weave Carbon Fiber material properties. The two fabrication methods used were autoclave and heat press (compression molding) methods. Each fabrication method used two cure cycles, a recommended cure cycle of 275°F for 1 hour and a modified cure cycle of 250°F for 1.5 hours. The exact product data …

Design And Fabrication Of A Ramjet Engine, Clinton C. Humphrey

Aerospace Engineering

In this report, the design and fabrication of the inlet to a ramjet engine is described. The inlet utilizes a single ramp and single sided three shock internal compression to slow the airflow from supersonic to subsonic speeds while providing maximum stagnation pressure to the combustor. The optimum angle for the inlet ramp is calculated to be 10° and it decelerates the airflow from Mach 3.3019 to Mach 0.5438. The stagnation pressure increases from 150 psi to 4.67 ksi. The material of the inlet is composed primarily of low carbon mild steel to accommodate the high pressure of the inlet.

Feasibility Of Cubesat Formation Flight Using Rotation To Achieve Differential Drag, Skyler M. Shuford

Aerospace Engineering

This paper presents the results of a study conducted to understand the feasibility of CubeSat formation flight. The mechanism for separation and formation studied was differential drag, achieved by rotating the CubeSats to give them different cross-sectional areas. Intuitively, lower altitude orbits provide much higher separation effects. Although the most influential orbital effects occur with maximum and minimum cross-sectional areas, an attitude-controlled and a tumbling CubeSat may provide enough differential drag to meet separation requirements of a mission. Formation flight is possible, but due to the non-linearity of the system, gain scheduling may be the most effective method of long …

Proof Of Concept For Propeller Performance Testing In The Cal Poly Wind Tunnel, Alex N. May, Clayton R. Green, Clinton J. Kirsop, Jason A. Schupp

Aerospace Engineering

The goal of this experiment was to execute a proof of concept for a potential propulsion systems laboratory. During the course of this experiment, a data acquisition system was designed, built, and tested in order to collect data from the Cal Poly 3x4 ft draw-down wind tunnel. By operating a brushless outrunner motor and propeller on the sting mount, data was collected for thrust, torque, RPM, current, voltage, and tunnel velocity. By obtaining data for each of these performance metrics, trends were analyzed to confirm the concept and apparatus was functional. The results of the experiment revealed that the concept …

Nozzle Design For The Supersonic Wind Tunnel Ramjet Attachment, Andrew Michael Carter

Aerospace Engineering

This document outlines the concept, design, and manufacturing stages of the nozzle section to the Ramjet Attachment. This project is a subsidiary of the thesis, Baseline Performance of Ramjet Engine”, developed by Harrison Sykes. The nozzle geometry is based off of theoretical calculations using Isentropic and Rayleigh line flow relations for a two-dimensional cross section. The nozzle sees an inlet temperature of 953 degrees Fahrenheit, pressure of 28 psi, and a Mach number of 0.356 after the combustion chamber. The nozzle section is a two foot long converging diverging nozzle to choke and accelerate the flow to achieve an exit …

Redesigned Aerospace Control System Platform For Laboratory Re-Purposing, Ryan W. Moskaluk

Aerospace Engineering

This senior project encompasses using an aircraft model in conjunction with the 3' by 4' low speed wind tunnel at Cal Poly San Luis Obispo. The aircraft model is controlled through piezoelectric actuators embedded inside the flexible tail structure via a PID controller. The objective for this project is to demonstrate the effect of tuning the individual PID controller gains with the aircraft model inside the low speed wind tunnel and to create an easy to use graphical user interface for doing so.

Incorporating Aluminum Honeycomb To Increase Efficiency Of U-Tube Removable Heat Exchanger, Daniel Soto, Daniel Corona

Aerospace Engineering

This report contains the results of attempting to improve on the results of Scott R. Sawyer and Alan M. L’Esperance research paper “Investigation of Paraffin Wax as an Energy Storage Medium Within a Shell-and-Tube Heat Exchanger.” The overall goal of the paper mentioned was to investigate the usefulness of wax as an energy storage medium. Scott R. Sawyer and Alan M. L’Esperance determined that “the amount of energy that can be released by the paraffin wax back to the airflow reaches a plateau, despite an increase in heating times.” They suggested that by surrounding the airflow tubes of a heat …

Paschen Breakdown In A Co2 Atmosphere, Matthew T. Stumbo

Aerospace Engineering

This report observes and analyzes the effect the pressure and gap distance have on the minimum positive breakdown potential between two parallel plate copper electrodes in both air and CO₂. Two gap distances, 0.57 cm and 2.44 cm, were used. Paschen Curves generated in air from these distances had a strong positive correlation with a Spearman correlation coefficient of 0.97. Curves generated in CO₂ had a Spearman correlation coefficient of 0.87. The strong correlation for both gases verifies Paschen's Law. The minimum breakdown potential in air was 361 ± 2 V at a pressure x gap distance …

Synergistic Effects Of Atomic Oxygen And Ultraviolet Radiation Exposure On Various Spacecraft Materials, Adrian L. Doan

Aerospace Engineering

The Aerospace Engineering Space Environments Laboratory at California Polytechnic State University features a ground-based system capable of generating atomic oxygen (AO) and vacuum ultraviolet (VUV) radiation environments, constructed by Max Glicklin in 2012. Experiments using three different spacecraft materials were conducted to test the individual and synergistic effects of these naturally occurring phenomena. Kapton HN functioned as a means to provide initial validation of the presence of AO and VUV radiation. Kapton HN also functioned as a test-fluence standard during testing of two other materials. These materials included aluminized beta cloth, with the non-aluminized side being tested, and Indium-Tin-Oxide (ITO) …

Thermal Vacuum Chamber Operation And Testing, Leila Tebyani

Aerospace Engineering

The purpose of this senior project is to understand the capabilities of the thermal vacuum chamber in the Space Environments Laboratory at California Polytechnic State University and compare the performance to thermal vacuum chambers used in the aerospace industry. The lowest temperature attained inside the chamber during an experiment at ambient pressure was -33°C. The lowest pressure reached by the vacuum chamber at the time of this project was 5e-5 Torr. This report also yields recommendations for integrating a demonstation of the effects of thermal variation in space on spacecraft components for the class AERO 471. A lit LED can …

Development Of Random Vibration Profiles For Test Deployers To Simulate The Dynamic Environment In The Poly-Picosatellite Orbital Deployer, Steve Furger

Aerospace Engineering

TestPODs and P-PODs have different structures with different resonant frequencies. This causes a change in the frequency response for CubeSats integrated into TestPODs compared to P-PODs. Adjusted random vibration profiles were developed for TestPODs to simulate the dynamic environment of the P-POD so CubeSats would have a consistent response in both deployers. Testing has shown that, with proper characterization of TestPODs and P-PODs, adjusted profiles can be used for TestPODs to simulate the P-POD dynamic environment.

Fin Flutter Analysis, Richard Bauer, Austin Hardman

Aerospace Engineering

This report summarizes the experimental process executed to study fin flutter characteristics. The experiment analyzed the influence of the relationship between structural dynamics and aerodynamics on flutter characteristics. Theoretical models were created in PATRAN/NASTRAN and FinSim for comparison to experimental results and to set the envelope of the physical experiments. The theoretical analysis predicted the occurrence of flutter near Mach 1 or Mach 5. The physical model was constructed of solid aluminum with machined holes for the inertial sensors. Two test runs were completed to collect data on the displacement of the fin in the supersonic wind tunnel. Additionally, the …

Creation And Analysis Of An Electric And Magnetic Model Of A Micro Ion Thruster, Maxwell Bodnar

Aerospace Engineering

This report explores the magnetic and electric fields within the Cal Poly Miniature Xenon Ion (MiXI) Thruster V3 in order to create a comprehensive electric and magnetic model of the plasma chamber to analyze and test the current thruster configurations and changes to the existing thruster. This model is used to analyze the operation and efficiency of the ion thruster and the plasma environment within the plasma chamber. This model explores the ionization and electron collision rates during operation of the thruster to measure the efficiency of the current thruster configuration, also determining the theoretical Isp and thrust of the …

Study Of Natural Composite Materials Square Beam Under Three Point Bending Test, Casey Wu

Aerospace Engineering

The purpose of this report is to summarize the findings on three point bending tests to try to find the optimum geometrical shape and layup configuration of a square beam composed of natural composites. The final project was entered into the SAMPE 2013 bridge building competition to compete internationally against other universities in the natural square beam category. The main focus of the bridge project is to compose it entirely of natural occurring fibers and other natural materials to create a “green” beam. The beams in the competition are tested under 3 point bending tests and will be scored based …

Construction And Testing Of A Quadcopter, David Roberts

Aerospace Engineering

No abstract provided.

Assessment For Completion Of Cp7 Integration With Revision 6 Avionics, Daniel Jennings

Electrical Engineering

he purpose of this project is the continuation of the CP7 CubeSat project, analysis for integration with new Avionics Systems, and to leave behind instruction for future work for completion of the satellite. CP7 is a satellite in development to support a mechanical and electrical system to experiment on particle damping in micro-gravity. The completion of this satellite needs to be prioritized more than it has been by the PolySat team to honor our work with Northrop Grumman, who have been supportive and helpful throughout the process. This work seeks to aid in the completion of this satellite, so that …

Integrated Collision Avoidance System Sensor Evaluation Final Design Project, Alex F. Graebe, Bridgette S. Kimball, Drew T. Lavoise

Mechanical Engineering

Following the development of Aircraft Collision Avoidance Technology (ACAT) by the National Aeronautics and Space Administration (NASA), a need arose to transition the life-saving technology to aid the general aviation community. Considering the realistic cost of implementation, it was decided that the technology should be adapted to function on any smartphone, using that device as an end-to-end solution to sense, process, and alert the pilot to imminent threats. In September of 2012, the SAS (Sense and Survive) Senior Project Team at California Polytechnic University (Cal Poly), San Luis Obispo was assigned the task of using smartphone technology to accurately sense …

A Generic Decision Making Framework For Autonomous Systems, Connor Lange

Master's Theses

With the rising popularity of small satellites, such as CubeSats, many smaller institutions previously incapable of developing and deploying a spacecraft have starting to do so. Institutions with a history of space flight, such as NASA JPL, have begun to put projects on CubeSats that would normally fly on much larger satellites. As a result, the institutions with space flight heritage have begun to port spacecraft software that was previously designed for much larger and more complex satellites to the CubeSat platform. Unfortunately for universities, who are the majority of all institutions devel- oping CubeSats, these ported systems are too …

Feasibility Of Microsatellite Active Debris Removal Systems, Karsten J. James

Master's Theses

Space debris has become an increasingly hazardous obstacle to continued spaceflight operations. In an effort to mitigate this problem an investigation of the feasibility of a microsatellite active debris removal system was conducted. Through proposing a novel concept of operation, utilizing a grapple-and-tug system architecture, and by analyzing each resultant mission phase in the frame of a representative example, it was found that microsatellite scale systems are capable of fulfilling the active debris removal mission. Analysis of rendezvous, docking, control and deorbit mission requirements determined that the design of a grapple-and-tug system will be driven by sizing of the propellant …

Rocket Fuel Pressurization, Sean Green, Joe Marcinkowski, Andrew Nahab

Mechanical Engineering

No abstract provided.

Design And Analysis Of Reusable Nozzles For Cal Poly’S Hybrid Rocket Lab, Cheyne Austin, Jose Vargas

Aerospace Engineering

Two nozzles were designed and constructed for testing in the Cal Poly propulsion laboratory to explore which nozzle was the most capable in producing the most thrust. A 15 degree and 30 degree converging-diverging nozzles were machined and tested. Theory suggest that a bell nozzle would be the most efficient since all of the gasses generated in the combustion chamber are directed and accelerated by the throat leave the nozzle traveling along the thrust axis. All of the momentum of the gasses are directed axially thus resulting in maximum thrust. Thrust should also be produced by the converging-diverging nozzle and …

Low-Cost Imu Implementation Via Sensor Fusion Algorithms In The Arduino Environment, Brandon Mccarron

Aerospace Engineering

A multi-phase experiment was conducted at Cal Poly in San Luis Obispo, CA, to design a low-cost inertial measurement unit composed of a 3-axis accelerometer and 3-axis gyroscope. Utilizing the growing microprocessor software environment, a 3-axis accelerometer and 3-axis gyroscope simulated 6 degrees of freedom orientation sensing through sensor fusion. By analyzing a simple complimentary filter and a more complex Kalman filter, the outputs of each sensor were combined and took advantage of the benefits of both sensors to improved results. Gyroscopic drift was removed in the pitch and roll axes using the Kalman filter for both static and dynamic …

Micrometeoroid Fluence Variation In Critical Orbits Due To Asteroid Disruption, Eliot Dan Aretskin-Hariton

Master's Theses

Micrometeoroids and orbital debris (MMOD) is a growing issue with international importance. Micrometeoroids are naturally occurring fragments of rock and dusk that exist throughout the solar system. Orbital debris is human made material like rocket bodies, paint flakes, and the effluent of spacecraft collisions. Even small MMOD particles on the order of 1 cm in diameter have the potential to destroy critical spacecraft systems. Because of this, MMOD is a threat to all spacecraft in orbit. Even governments that most sternly oppose US international policy have a stake when it comes to minimizing MMOD flux. Space-based assets are essential to …

Design, Fabrication, And Testing Of An Emr Based Orbital Debris Impact Testing Platform, Jeffrey J. Maniglia Jr.

Master's Theses

This paper describes the changes made from Cal Poly’s initial railgun system, the Mk. 1 railgun, to the Mk. 1.1 system, as well as the design, fabrication, and testing of a newer and larger Mk. 2 railgun system. The Mk. 1.1 system is developed as a more efficient alteration of the original Mk. 1 system, but is found to be defective due to hardware deficiencies and failure, as well as unforeseen efficiency losses. A Mk. 2 system is developed and built around donated hardware from the Naval Postgraduate School. The Mk. 2 system strove to implement an efficient, augmented, electromagnetic …

Improvement Of Electromagnetic Railgun Barrel Performance And Lifetime By Method Of Interfaces And Augmented Projectiles, Aleksey D. Pavlov

Master's Theses

Several methods of increasing railgun barrel performance and lifetime are investigated. These include two different barrel-projectile interface coatings: a solid graphite coating and a liquid eutectic indium-gallium alloy coating. These coatings are characterized and their usability in a railgun application is evaluated. A new type of projectile, in which the electrical conductivity varies as a function of position in order to condition current flow, is proposed and simulated with FEA software. The graphite coating was found to measurably reduce the forces of friction inside the bore but was so thin that it did not improve contact. The added contact resistance …