Engineering Commons^™

System Design Considerations And The Feasibility Of Passively Compensated, Permanent Magnet, Iron-Core Compulsators To Power Small Railgun Platforms, Collin Taylor Macgregor

Master's Theses

This thesis provides insight into the different aspects of compulsator design for use with railgun systems. Specifically, the design space is explored for passively compensated, permanent magnet iron-core compulsators. Seven design parameters are varied within a compulsator model developed for the Cal Poly Compulsator (CPCPA). The Matlab code for this model is included within the appendix. Efforts were made to compare and validate this compulsator model to published data from existing systems. The compulsator model was found to match closely with discharge pulse length, but resulted in lower values for peak current and projectile velocity by 50% and 30% respectively …

A Lateral Flow Smart Phone Image Analysis Diagnostic, Christina Holly Tyrrell

Master's Theses

A low cost compact diagnostic has many implications in today’s society. Smart phone technology has exponentially grown and with it the imaging capabilities associated with smart phones. The goals of this research are i) to determine the feasibility of combining in the field smart phone images with color dependent assay results, ii) to develop a MatLab® image analysis code to analyze these results, and iii) compare limits of detection between the un-aided eye and MatLab® image analysis software.

Orange G dye is used to create a stock solution and subsequent titers for analysis. Autocad is used to design an assay …

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 …

Constructing And Optimizing A Single Wafer Solar Cell Array In The Microfabrication Lab At California Polytechnic State University At San Luis Obispo, Rod Marstell

Master's Theses

CONSTRUCTING AND OPTIMIZING A SINGLE WAFER SOLAR CELL ARRAY IN THE MICROFABRICATION LAB AT CALIFORNIA POLYTECHNIC STATE UNIVERSITY AT SAN LUIS OBISPO

Solar cells are more and more becoming a significant source of energy in the world today. They are used to power entire buildings as well as small devices and everything in between, and are utilized all around the world. Smaller solar devices, such as hearing aid battery chargers, cost a lot of money relative to the monetary wealth in third-world countries. For this purpose, a less expensive, more efficient solar cell array should be developed.

This study contains …

Weighing The Financial And Sustainable Benefits Of High Performance Structures In Seismically Active Regions, Alia Talina Barajas

Master's Theses

This thesis investigated the potential advantages and disadvantages of high performance structures by comparing the financial and environmental impacts of a performance based four-story office building to one designed to meet minimum code-level requirements.

To generate a comparison, the lateral system of a four-story structure utilizing buckling restrained braced frames was designed to meet code-level requirements per the American Society of Civil Engineers’ Minimum Design Loads for Buildings and Other Structures (ASCE 7-05) and again to meet the immediate occupancy criteria defined by ASCE 41-06 Seismic Rehabilitation of Existing Buildings. The following was then performed:

• Test the structural performance of …

Metamaterial Enhanced Wireless Power Transmission System, Travis Jade Heffernan

Master's Theses

Nikolai Tesla's revolutionary experiments demonstrated the possible benefits of transmitting power wirelessly as early as 1891. Applications for the military, consumers, emergency personnel, remote sensors, and others use Tesla’s discovery of wireless power. Wireless power transmission (WPT) has the potential to be a common source of consumable energy, but it will only receive serious consideration if the transmit and receive systems are extremely efficient and capable of delivering usable amounts of power. Research has been conducted to improve the efficiency and performance of nearly every aspect of WPT systems, but the relatively new field of metamaterials (MTMs) has yet to …

Surgical Tooling Designed For The Direct Anterior Approach To Total Hip Arthroplasty, Jon-Peter Meckel

Master's Theses

Surgical Tooling Designed for the Direct Anterior Approach to Total Hip Arthroplasty Jon-Peter Meckel

Total hip arthroplasty (THA) is becoming more and more common in the US as people continue to live longer and more active lives. The main reason that a THA is required is due to the “wear and tear” affliction of osteoarthritis, which in the year 2000 had at least 3% of the population over 30 showing symptoms. A revitalized approach to THA is the direct anterior approach, or Smith-Petersen approach, which limits the amount of musculature affected by the surgery and creates a very stable joint …

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 …

The Fabrication & Characterization Of An Electrokinetic Microfluidic Pump From Su-8, A Negative Epoxy-Based Photoresist, Nash Anderson

Master's Theses

Microfluidics refers to manipulation, precise control, and behavior of fluids at the micro and nanoliter scales. It has entered the realm of science as a way to precisely measure or mix small amounts of fluid to perform highly controlled reactions. Glass and polydimethylsiloxane (PDMS) are common materials used to create microfluidic devices; however, glass is difficult to process and PDMS is relatively hydrophobic. In this study, SU-8, an epoxy based (negative) photoresist was used to create various electrokinetic microfluidic chips. SU-8 is commonly used in microelectromechanical design. Spin coating of various SU-8 formulations allows for 1 μm to 100 μm …

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 …

Applications Of Artificial Neural Networks To Synthetic Aperture Radar For Feature Extraction In Noisy Environments, David James Roberts

Master's Theses

It is often that images generated from Synthetic Aperture Radar (SAR) are noisy, distorted, or incomplete pictures of a target or target region. As the goal for most SAR research pertains to automatic target recognition (ATR), extensive filtering and image processing is required in order to extract the features necessary to carry out ATR. This thesis investigates the use of Artificial Neural Networks (ANNs) in order to improve upon the feature extraction process by laying the foundation for ANN SAR ATR algorithms and programs. The first technique investigated is that of an ANN edge detector designed to be invariant to …

Seismic Performance Comparison Of A Fixed-Base Versus A Base-Isolated Office Building, Nicholas Reidar Marrs

Master's Theses

The topic of this thesis is base isolation. The purpose of this thesis is to offer a relative understanding of the seismic performance enhancements that a typical 12-story steel office building can achieve through the implementation of base isolation technology. To reach this understanding, the structures of a fixed-base office building and a base-isolated office building of similar size and layout are designed, their seismic performance is compared, and a cost-benefit analysis is completed. The base isolation system that is utilized is composed of Triple Friction Pendulum (TFP) bearings.

The work of this thesis is divided into four phases. First, …

Seismic Rehabilitation Of Steel Moment Frames Vulnerable To Soft-Story Failures Through Implementation Of Rocking Cores, Juan Carlos Sanchez

Master's Theses

During seismic events, inefficient steel moment frame building systems may exhibit soft-story failures. This thesis focuses on development and validation of a seismic retrofit strategy for avoiding soft-story failures in low-rise and mid-rise steel moment frame buildings. The considered retrofit strategy consists of a sufficiently stiff Rocking Core (RC) pinned to the foundation and pin connected to the existing frame. For demonstration purposes, two representative benchmark steel moment frames, which are modified from the three- and nine-story pre-Northridge steel moment frames designed for Los Angeles in the SAC Steel Project, are considered. Finite Element (FE) models of the benchmark buildings …

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 …

Computational Modeling To Evaluate Helical Electrode Designs For Use In Vagus Nerve Stimulation, Anthony W. Cowley

Master's Theses

An estimated 0.5% of world’s population has been diagnosed with epilepsy. Of these patients 20-30% will be unable to achieve seizure control with anti-epileptic drugs. Vagus nerve stimulation (VNS) may be an appropriate treatment option for some patients with pharmaceutically refractory, partial-onset seizures.

VNS therapy uses a helical electrode to interface between the implantable pulse generator and the vagus nerve. While there have been several studies related to the mechanical and electrical safety of such electrodes, little work has been done toward understanding the effectiveness of the helical electrode in nerve stimulation. A better understanding of the voltage field and …

Multiple Input Single Output (Miso) Tablet/ Phone Charger, Kevin Wong

Master's Theses

This thesis entails the design and implementation of a multiple input single output (MISO) DC-DC converter using the flyback topology to charge tablets/ smartphones or any USB powered portable device. The MISO converter will enable the use of various renewable energy sources such as a solar panel/ rechargeable battery combination, bicycle dynamo, hydroelectric power, and wind turbine. This paper will cover the design, simulations, and test results of the MISO converter. The flyback topology was chosen due to its low part count and its efficiency at low power. The proposed converter has a nominal 12V input to output USB 2.0 …

Real Time Visibility Culling With Hardware Occlusion Queries And Uniform Grids, Ilya Iseletsk Seletsky

Master's Theses

Culling out non-visible portions of 3D scenes is important for rendering large complex worlds at an interactive frame rate. Past 3D engines used static prebaked visibility data which was generated using complex algorithms. Hardware Occlusion Queries are a modern feature that allows engines to determine if objects are invisible on the fly. This allows for fully dynamic destructible and editable environments as opposed to static prebaked environments of the past. This paper presents an algorithm that uses Hardware Occlusion Queries to cull fully dynamic scenes in real-time. This algorithm is relatively simple in comparison to other real-time occlusion culling techniques, …

Design And Modeling Of Centralized Distribution Network For The Dc House Project, Harpreet S. Bassi

Master's Theses

This thesis focuses on the design, modeling, simulation, and performance evaluation of Centralized Distribution Network for the DC House Project. Power System Computer Aided Design (PSCAD) is used to model a Centralized PV Source, Battery Bank, and Distribution Network for 25 DC Houses. Design and modeling of each component in the proposed system are described. For the performance evaluation, emphasis is on voltage stability and system reliability under different operating conditions. Results from the simulation demonstrate the feasibility of the proposed Centralized Distribution Network for the DC House Project to support the houses during non-generation periods and distribution network voltage …

Manufacturing Execution System (Mes) An Examination Of Implementation Strategy, Riley F. Elliott

Master's Theses

The priorities of executing the manufacturing orders generated by an MRP system are often in operational conflicts with the dynamics of the manufacturing floor. It is not uncommon for a given manufacturing order to reach the shop floor several weeks or longer after being "opened" by an MRP system where it may face a chaotic case of large queues, machine down-time, parts shortage, scrap problems and other resource management constraints. Many companies have resorted to the Manufacturing Execution System (MES) software solution to resolve these problems. This method first gained popularity in mid-90’s within the semiconductor industry. An MES approach …

Dairy Manure Flushwater Treatment By Packed-Bed Anaerobic Digesters, Neal Cary Adler

Master's Theses

Wastewater treatment performance of three pilot-scale packed-bed anaerobic digesters with walnut shell medium was researched for treating dairy freestall barn flushwater. Reciprocation mixing was evaluated as a means to lessen channelization in the media bed and to improve biogas production and organic matter removal at ambient temperatures. Reciprocation has been used in biological nitrogen removal systems to introduce air into the system to repeatedly oxygenate nitrifying biofilm along with mixing (Behrends et al. 2003), but the anaerobic systems benefit from mixing. Two tanks were used in each system, where one was full and one was empty at any given time. …

Nutrient Removal Using Microalgae In Wastewater-Fed High Rate Ponds, Matthew N. Rodrigues

Master's Theses

This thesis discusses the mechanisms associated with the removal of organic matter, nitrogen and phosphorus in wastewater-fed high rate algae ponds (HRAP) designed to operate as triplicates. Research was conducted at the San Luis Obispo Water Reclamation Facility (SLOWRF) as a pilot-scale study of nine 30-square meter ponds one foot in depth. During period of study, triplicates were operated at hydraulic retention times (HRT) of 4, 3 or 2-days. Main objectives for the study were to determine minimum HRTs required to achieve secondary and tertiary treatment. Experimental conditions such as CO₂ supplementation, nighttime aeration and operation of ponds in …

Applied Hw/Sw Co-Design: Using The Kendall Tau Algorithm For Adaptive Pacing, Kenneth W. Chee

Master's Theses

Microcontrollers, the brains of embedded systems, have found their way into every aspect of our lives including medical devices such as pacemakers. Pacemakers provide life supporting functions to people therefore it is critical for these devices to meet their timing constraints. This thesis examines the use of hardware co-processing to accelerate the calculation time associated with the critical tasks of a pacemaker. In particular, we use an FPGA to accelerate a microcontroller’s calculation time of the Kendall Tau Rank Correlation Coefficient algorithm. The Kendall Tau Rank Correlation Coefficient is a statistical measure that determines the pacemaker’s voltage level for heart …

Surfactant Formulations For Water-Based Processing Of A Polythiophene Derivative, Cameron Dean Danesh

Master's Theses

Conjugated polymers are semiconducting materials that are currently being researched for numerous applications from chemical and biological sensors to electronic devices, including photovoltaics and transistors. Much of the novel research on conjugated polymers is performed in academic settings, where scientists are working to prepare conjugated polymers for commercially viable applications. By offering numerous advantages, inherent in macromolecular materials, conjugated polymers may hold the key to cheap and environmentally friendly manufacturing of future electronic devices. Mechanical flexibility, and solvent-based coating processes are two commonly cited advantages. Transitions in the backbone conformation of polythiophenes (PT) in organic solvents have been widely observed …

The Effect Of A Triphasic Pulse On Scs To Icd Crosstalk, Ryan James Wensley

Master's Theses

It is a known problem that a Spinal Cord Stimulator (SCS) can interact with an Implantable Cardioverter Defibrillator (ICD) when both devices are implanted in the same patient. Interactions between the SCS and ICD can cause inappropriate therapy which can be harmful to the patient. While ICD devices have a distinct narrowband sensing bandwidth, the pulse configurations that current SCS devices deliver were not designed with this frequency region in mind. In this thesis, I recommend a new pulse configuration for SCS devices that will minimize the interaction between the two devices. I produce a theoretical equation for each pulse …

Designing Anti-Islanding Detection Using The Synchrophasor Vector Processor, Ruth Christiana Huang

Master's Theses

ABSTRACT

Designing Anti-Islanding Detection Using the Synchrophasor Vector Processor

Ruth Huang

The need for distributed generation (DG) has become more and more popular because of the adverse effects of fossil fuels and the fear of running out of fossil fuels. By having DG, there are less transmission losses, voltage support, controllability of the system, decreased costs in transmission and distribution, power quality improvement, energy efficiency, and reduced reserve margin. The adverse effects of DG are voltage flicker, harmonics, and islanding. Islanding occurs when the DG continues to energize the power system when the main utility is disconnected. Detecting islanding is …

A Stand-Alone Methodology For Data Exploration In Support Of Data Mining And Analytics, Michael Gage

Master's Theses

With the emergence of Big Data, data high in volume, variety, and velocity, new analysis techniques need to be developed to effectively use the data that is being collected. Knowledge discovery from databases is a larger methodology encompassing a process for gathering knowledge from that data. Analytics pair the knowledge with decision making to improve overall outcomes. Organizations have conclusive evidence that analytics provide competitive advantages and improve overall performance. This paper proposes a stand-alone methodology for data exploration. Data exploration is one part of the data mining process, used in knowledge discovery from databases and analytics. The goal of …

The Effect Of 2d And 3d Menus On Memory Retention In User Interface Design, Angela Michelle Muscat

Master's Theses

The increasing use of 3D user interface elements, particularly 3D menus, demonstrates the need to expand research in the field of Human Computer Interaction (HCI) as it pertains to 3D user interfaces. The results of this thesis contribute to the understanding of the cognitive impacts of using 3D menus. Multiple application areas for 3D menus have been identified where memory retention is a critical success factor, but little research has been done in the area of memory retention for 3D menus. The purpose of this thesis is to investigate if the use of 3D carousel menus increases retention of information …

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 And Development Of A Stair Ascension Assistive Device For Transfemoral Amputees, Casey Michael Barbarino

Master's Theses

Transfemoral amputees around the world experience increased difficulty in climbing stairs due to lack of muscle, balance, and other factors. The loss of a lower limb greatly diminishes the amount of natural force generation provided that is necessary to propel oneself up stairs. This study investigated possible solutions to the problem of stair ascension for transfemoral amputees by the means of designing and developing an externally attachable device to a prosthesis. The number of amputations from military service has greatly increased since 2008, which shows there is a clear need for assistive devices (Wenke, Krueger, & Ficke, 2012). With the …

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 …