Engineering Commons^™

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 …

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 …

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 …

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 …

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.

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 …

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 …

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 …

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.

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 …

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 …

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 …

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) …

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.

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.

Construction And Testing Of A Quadcopter, David Roberts

Aerospace Engineering

No abstract provided.

Establishing Mission Requirements Based On Consideration Of Aircraft Operations, Robert A. Mcdonald

Aerospace Engineering

The design requirements for a next-generation commercial aircraft can do much to secure its fate as a success or failure. New aircraft are often designed to meet or surpass the capabilities of an existing aircraft they are intended to replace. However, in the case of unconventional aircraft, this could lead to significant overdesign resulting in nonviable concepts. Instead, a method of analyzing observed aircraft use is presented with the intent of establishing a set of requirements based on replacing aircraft utility instead of capability. Two aircraft in the commercial fleet are used as example cases, and launch customers for each …

Influence Of Wing Span On The Aerodynamics Of Wings In Ground Effect, Sammy Diasinos, Tracie J. Barber, Graham Doig

Aerospace Engineering

A computational fluid dynamics study of the influence of wing span has been conducted for an inverted wing with endplates in ground effect. Aerodynamic coefficients were determined for different spans at different ground clearances, highlighting a trend for shorter spans to delay the onset of both separation and resulting loss of negative lift. The vortices at the wing endplates were not observed to change significantly in terms of strength and size; thus, at shorter spans, their influence over a larger percentage of the wing helped the flow stay attached and reduced the severity of the adverse pressure gradient which invokes …

Design Of A Specimen Fixture For Impact Resistance Testing In An Instron Dynatup 8250 Drop Weight Impact Tester, Daniel Alejandro Barath

Aerospace Engineering

The purpose of this report is to outline the path and methods used to design a specimen fixture for the testing and analysis of fiber reinforced composites subjected to impact loading. This design is done in support of the California Polytechnic State University in San Luis Obispo Structures and Composites Laboratory. The design request was made at the request of Dr. Eltahry Elghandour to support the graduate students Kodi A. Rider and Y. Vanessa Wood in their master’s degree thesis projects.

The design request involved the design of a specimen fixture compatible with the existing impact apparatus located in the …

Smore Revision: Ignition And User Interface, Arash Mehrparvar

Aerospace Engineering

The Static Methanol Oxygen Rocket Engine (SMORE) has undergone several revisions since its inception. This latest revision aimed to increase startup reliability and user safety in the operation of the rocket. The implementation of maintenance procedures, safeguards in the ignition system, as well as construction of a new control box and redesign of the igniter itself have accomplished these goals while keeping costs down and without modifying the current rocket setup. Startup reliability has increased drastically, so long as all other rocket setup procedures are followed properly. 250 subsequent firings of the rocket have proven an igniter reliability of more …

Flow Uniformity Calibration Of Amelia's Circulation Control Wings, Eric N. Paciano, Johnathan A. Lichtwardt, David D. Marshall, Kristina K. Jameson, Robert K. Fong

Aerospace Engineering

This paper details the extensive effort required to achieve uniform now from the AMELIA wind tunnel model's circulation control wings. Performed in September of 2011 in the Fluid Mechanics Lab at NASA Ames Research Center, the calibration required a 500hp instrument-quality air compressor capable of delivering 250 CFM at pressures greater than 70 psL It was found that the geometery within AMELIA's circulation control supply plenums produced highly vortlcal flow, resulting in poor circulation control performance as measured by traversing external and stationary internal total pressure probes, as well as surface oil now. Adjustments were made within AMELIA to the …

Stol Performance Of Cal Poly's Amelia, Johnathan A. Lichtwardt, Eric N. Paciano, David D. Marshall, Kristina K. Jameson

Aerospace Engineering

Results from Cal Poly's recent wind tunnel test in the 40-by 80-foot test section at the National Full-Scale Aerodynamics Complex (NFAC) at NASA Ames Research Center are presented. AMELIA, the Advanced Model for Extreme Lift and Improved Aeroacoustics, is the first full-span cruise efficient short take-off and landing (CESTOL) model incorporating leading-and trailing-edge blowing wing circulation control and over-the-wing mounted turbine propulsion simulators (TPS) to date. Testing of the 10 foot span model proved successful and was the result of a 5-year NASA Fundamental Aeronautics Program Research Announcement. All of the results associated with Cal Poly's effort will be available …

Cal Poly's Amelia 10 Foot Span Hybrid Wing-Body Low Noise Cestol Aircraft Wing Tunnel Test And Experimental Results Overview, Kristina K. Jameson, David D. Marshall, Robert Ehrmann, Jonathon A. Lichtwardt, Eric N. Paciano, Robert J. Englar, William C. Hornes

Aerospace Engineering

A collaboration between California Polytechnic Corporation with Georgia Tech Research Institute (GTRI) and DHC Engineering worked on a NASA NRA to develop predictive capabilities for the design and performance of Cruise Efficient, Short Take-Off and Landing (CESTOL) subsonic aircraft. The work presented in this paper gives details of a large scale wind tunnel effort to validate predictive capabilities for this NRA for aerodynamic and acoustic performance during takeoff and landing. The model, Advanced Model for Extreme Lift and Improved Aeroacoustics {AMELIA), was designed as a 100 passenger, N+2 generation, regional, cruise efficient short takeoff and land (CESTOL) airliner with hybrid …

Enabling Rapid Conceptual Design Using Geometry-Based Multi-Fidelity Models In Vsp, Joel B. Belben, Robert A. Mcdonald

Aerospace Engineering

Four types of reduced fidelity or degenerate geometric representations have been defined and implemented in VSP for the purpose bridging the gap between conceptual design and analysis. They are Degenerate Surface, Degenerate Plate, Degenerate Stick, and Degenerate Point, corresponding to three-, two-, one-, and zero-dimensional representations of underlying geometry, respectively. The information contained in these representations was targeted specifically at lifting line theory, vortex lattice, equivalent beam, and equivalent plate methods, but could be used for other analysis techniques. The ability to output this information in both csv and Matlab file formats has been implemented in VSP. Ongoing work seeks …

Electric Motor Modeling For Conceptual Aircraft Design, Robert A. Mcdonald

Aerospace Engineering

Electric motors have achieved very high efficiency and reliability; and in some cases, very high specific power. As the energy storage capabilities of batteries and fuel cells advance, these technologies are increasingly being considered for aircraft primary propulsion. In order to design electric aircraft, aircraft designers must be able to understand and model the performance characteristics of electric motors. Most electric machine modeling techniques either ignore potentially important phenomena or require an extreme level of detail undesirable for conceptual aircraft design. In this paper, a compromise approach is proposed which can capture the salient details of motor performance without requiring …

Solar Energy Collection Analysis Tool For Conceptual Aircraft Design, Grant M. Glazebrook, Robert A. Mcdonald

Aerospace Engineering

As battery energy storage and solar cell technology improve, solar aircraft are increasingly being considered for high altitude long endurance missions. Although solar vehicles may theoretically remain on station indefinitely using the sun as a power source, their design and feasibility is sensitive to mission planning details as specific as the time history of the vehicle’s deck orientation relative to the sun; the energy available for capture by the on-board solar array is governed by the solar incidence angle, and at certain orientations, the vehicle may cast shadows on itself and further reduce its energy capture capabilities. To quantify these …