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Full-Text Articles in Engineering

One-Pin 32 Khz Low-Power Crystal Oscillator, Aaron Plata-Ruiz Jun 2011

One-Pin 32 Khz Low-Power Crystal Oscillator, Aaron Plata-Ruiz

Electrical Engineering

This design is a one-pin, 32 kHz, low-power, crystal oscillator suitable for battery-operated systems. The design is based on a design published by Ali E Zadeh, “A Micropower, Battery-Operated, One-Pin Crystal Oscillator”, but redesigned for standard positive power supply configuration, which is suitable for typical n-well CMOS process.


Heart-Rate Monitoring Control System Using Photoplethysmography (Ppg), Wesley Nguyen, Ryan Horjus Jun 2011

Heart-Rate Monitoring Control System Using Photoplethysmography (Ppg), Wesley Nguyen, Ryan Horjus

Electrical Engineering

No abstract provided.


Design And Simulation Of V2g Bidirectional Inverter And Dc-Dc Converter, Allan Agatep, Mason Ung Jun 2011

Design And Simulation Of V2g Bidirectional Inverter And Dc-Dc Converter, Allan Agatep, Mason Ung

Electrical Engineering

As plug-in hybrid electric vehicles (PHEV) become more popular, the utility companies are forced to feed the grid more electricity. However, these PHEVs are capable of providing power to the grid when they are parked serving as ancillary systems for grid regulation (V2G). Using a system based on photovoltaic (PV) technology, a design for a bidirectional inverter with LCL filter, and a bidirectional dc-dc with a constant current controller, was constructed using LTspice. Various papers were researched and analyzed to determine applicable designs for components. Simulations show the designs are capable of bidirectional power transfer. ETAP simulations show that delivering …


An Investigation Into Ultrasonic Communication For Near-Body Networks, Eric Joshua Escudero Jr., Gursewak Singh Rai Jun 2011

An Investigation Into Ultrasonic Communication For Near-Body Networks, Eric Joshua Escudero Jr., Gursewak Singh Rai

Electrical Engineering

The following report presents a study of body-area, free-space ultrasonic communication system. Two analog communication systems are investigated. The initial communications system setup relies upon the amplitude modulation (AM) techniques to transmit the signal. Such a system is prone to noise since the amplitude of the signal is directly affected by distance and the signal strength will deteriorate. The secondary communication system involves utilizing frequency modulation (FM). This method avoids the issue of losing information due to amplitude deterioration, but encounters delay issues. The main hardware components used in the approach outlined include ultrasonic transducers (UTs) used for both transmitting …


Programmable Solid State 12ax7 Triode Gain Stage, Ian Campbell Jun 2011

Programmable Solid State 12ax7 Triode Gain Stage, Ian Campbell

Electrical Engineering

This project demonstrates the viability of vacuum tube replacements made from solid state technology and programmable logic. A collection of operational amplifiers, digital converters and a field programmable gate array (FPGA) achieve this goal. The project emulates a 12AX7 vacuum tube triode as it would operate in a Fender Champ guitar amplifier. While the prototype works specifically with the Fender Champ, minor modifications could provide the versatility for operation in different amplifiers, including high end vintage hi-fi equipment. The addition of a micro controller into these amplifiers allows for the use of digital filtering and effects while not requiring modifications …


Wireless Sensor Network For Energy And Environmental Monitoring: Helping Old Buildings Go Green, Jacob Power Jun 2011

Wireless Sensor Network For Energy And Environmental Monitoring: Helping Old Buildings Go Green, Jacob Power

Electrical Engineering

Today, the rising cost of energy and social trend of “going green” has put increasing pressure on commercial property owners to improve the efficiency of their investments. There is good reason for this, too. In the State of California, office buildings represent the single largest user of energy in the commercial sector. This project consisted of the design, implementation, construction, testing, and deployment of a wireless sensor network for energy and environmental monitoring in retrofit commercial office installations. The analyzed data generated by this system can be used by building management and owners to identify areas of inefficiency within the …


Current Tracking Power Supply For Sensor Calibration, Joshua Brookley Jun 2011

Current Tracking Power Supply For Sensor Calibration, Joshua Brookley

Electrical Engineering

This report highlights the steps taken to design and develop a constant 5V power supply capable of tracking load current. The background of its previous design, its necessary specifications and steps taken to achieve specifications are highlighted throughout the report. The report also contains conclusions and final recommendations for the design chosen, including its strengths and drawbacks.


Discrete Alarm Clock, Travis Moore, Collin Barth Jun 2011

Discrete Alarm Clock, Travis Moore, Collin Barth

Electrical Engineering

The standard alarm clock, as used daily by millions worldwide, has clear room for modification and improvement. This paper documents an implementation that rectifies many of these flaws. Improvements include adjustable snooze length, an IR remote for ease of use, and an RF headset for discrete alarm use or potential incorporation into a device much like a hearing aid. The processes involved in creating a digital alarm clock, as well as the obstacles met in the implementation of the enhanced design, are detailed within.


Rfid Techniques For Passive Electronics, Ryan Behr, David Cobos Jun 2011

Rfid Techniques For Passive Electronics, Ryan Behr, David Cobos

Electrical Engineering

No abstract provided.


Smooth Ternary Signaling For Deep-Submicron(Dsm) Buses, Robert Endicott Hanson, Ryan Ian Fullerton Jun 2011

Smooth Ternary Signaling For Deep-Submicron(Dsm) Buses, Robert Endicott Hanson, Ryan Ian Fullerton

Electrical Engineering

This project demonstrates the error mitigating effects of using a three-level “smooth ternary” signal on a Deep-Submicron(DSM) bus with large inter-wire capacitance. An RC circuit used to simulate and exaggerate (for easier testing) the charging and discharging of the DSM bus. An encoder stage translates binary input data into a three-level signal before sending it to the bus. A decoder stage then translates the three-level signal back to binary that is ideally identical to the original signal. Our results show that the three-level signal has much cleaner transitions than a traditional binary signal. A few glitches that appeared when decoding …


Energy Harvesting From Elliptical Machines Using Four-Switch Buck-Boost Topology, Alvin Jay Hilario May 2011

Energy Harvesting From Elliptical Machines Using Four-Switch Buck-Boost Topology, Alvin Jay Hilario

Master's Theses

This thesis presents the topic of using the Four-Switch Buck-Boost topology as a DC-DC converter for the Energy Harvesting from Elliptical Machines Project. The project works toward providing a modular synchronous power generation system. Due to the dynamic and sporadic output voltage and power characteristics of the Precor elliptical machine, the system requires a DC-DC converter as a voltage preregulator. The inherent wide input range, high efficiency, and low parts cost of this converter well suit the application. This paper further discusses other topologies and their shortcomings, as well as characterizes the Precor elliptical machine and Enphase Microinverter for interfacing. …


Elliptical Machine Dc-Dc Converter For The Energy Harvesting From Exercise Machines Project, Greg Hollister May 2011

Elliptical Machine Dc-Dc Converter For The Energy Harvesting From Exercise Machines Project, Greg Hollister

Electrical Engineering

Designing a DC/DC Converter for the Cal Poly Energy Harvesting from Exercise Machines project requires special attention to the unique operating characteristics of the source and the load. An elliptical machine powered by a person exercising comprises the source, while an AC Inverter makes up the load. This project attempts to integrate the two devices with a custom DC/DC Converter in order to ultimately deliver power back into the power grid.


Design And Analysis Of A Wind Energy Harvesting Circuit Using Piezoelectric Polymers, Jameson J. Thornton Apr 2011

Design And Analysis Of A Wind Energy Harvesting Circuit Using Piezoelectric Polymers, Jameson J. Thornton

Master's Theses

This thesis investigates a relatively new method for harvesting wind energy by using flexible piezoelectric polymers with additional sails to increase their ability to harvest wind energy. This paper also introduces a new topology deemed the “stacked buck” that allows for multiple inputs to a system with a single output. Derivations and analysis detail the workings of the “stacked buck” with a laboratory test to show a working model. This paper also reports another experiment done in a wind tunnel to analyze the capability of the piezoelectric polymers as sources to the “stacked buck” topology with measurements of the power …


Led Spotlight, Eric Toussaint Mar 2011

Led Spotlight, Eric Toussaint

Electrical Engineering

This report details the development and construction of an LED spotlight useable in a theatrical or architectural setting. In depth background information, initial design concepts, lighting instrument specifications, assembly, testing, and conclusions from results are highlighted in this document. Project goals include efforts to support more energy efficient lighting in the arts and general lighting applications and a decrease in overall costs for energy used in all dramatic and architectural lighting applications.


Universal Engineering Programmer – An In-House Development Tool For Developing And Testing Implantable Medical Devices In St. Jude Medical, Khoa Tat Do Mar 2011

Universal Engineering Programmer – An In-House Development Tool For Developing And Testing Implantable Medical Devices In St. Jude Medical, Khoa Tat Do

Master's Theses

During development and testing of the functionality of the pacemaker and defibrillator device, engineers in the St. Jude Medical Cardiac Rhythm Management Division use an in-house development tool called Universal Engineering Programmer (UEP) to ensure the device functions as expected, before it can be used to test on an animal or a human during the implantation process. In addition, some applications of UEP are incorporated into the official releases of the device product. UEP has been developed and used by engineers across departments in the St. Jude Medical Cardiac Rhythm Management Division (CRMD). This thesis covers the flexible and reusable …


Electric Guitar Amplifier With Digital Effects, Shawn Garrett Feb 2011

Electric Guitar Amplifier With Digital Effects, Shawn Garrett

Computer Engineering

During the course of this project, the research and development of an electric guitar amplifier was undertaken. This amplifier is divided into three distinct sections. The power distribution circuitry provides the proper voltages to safely operate all necessary components. The DSP and digital effects stage provides processing and allows the user to add digital effects to the original guitar sound. The amplification stage increases the power of the input signal to drive a loudspeaker. Due to several setbacks throughout the course of this project, the overall amplifier was not completed. All three of the sections were developed to working functionality, …


Aether, Thomas Cameron, Kristine Colton, Daren Childers Jan 2011

Aether, Thomas Cameron, Kristine Colton, Daren Childers

Electrical Engineering

Aether is a RC-style autonomous air vehicle that utilizes GPS positioning along with a wireless communication system to achieve a computer-controlled flight.

This report will incorporate the acquisition, design, integration, implementation and testing phases of the UAV development. Furthermore a discussion of troubleshooting as well as improvements for future projects will be included.


Hydro-Electric Generation System For The Dc House Project, Dennis Kwan, Mitchell Krug Jan 2011

Hydro-Electric Generation System For The Dc House Project, Dennis Kwan, Mitchell Krug

Electrical Engineering

This paper focuses on the design, integration, and construction of a system that harnesses energy from flowing water. The system will be used in conjunction with the DC House Project. The proposed system employs a DC generator and DC-DC Boost-converter to provide electricity to the DC House at approximately 200-300W. Results of the testing and measurement show that the goal of the system is feasible, but currently limited. The generator could not output the specified power. Details of the design, along with ideas for further improvement, are presented in this report.


Wireless Energy Transfer, Ryan Sasur Jan 2011

Wireless Energy Transfer, Ryan Sasur

Electrical Engineering

Phones are now an integral component in the daily lives of people. Smartphones give access to movies, internet, and even books. This versatility and increased use can also lead to a shorter battery life. A phone with video viewing capabilities will be a heavy load on the unit’s battery. With phones utilizing 3G and 4G technology, even heavier demands are placed on the battery. As technology improves even further to provide for a larger entertainment experience on the phone, this could also lead to further battery degradation if the current battery situation isn’t addressed. To have a fully operational phone …


Auto Dialer Wireless Smoke Detector/Alarm System, Manny Linhares Dec 2010

Auto Dialer Wireless Smoke Detector/Alarm System, Manny Linhares

Electrical Engineering

Smoke Detectors/Alarms save the lives of over sixty percent of people each year in the United States. Most of the existing homes are still fitted with the normal smoke detectors either running out of the 120V ac wiring or out of a 9V dc battery. These alarms are perfectly fine to alert residents if there is a fire while they are home. But for people who are away from home when a fire occurs, it would be nice if they could be alerted automatically of such an occurrence and therefore be able to act upon the event by either calling …


Asynchronous Mips Processors: Educational Simulations, Robert L. Webb Aug 2010

Asynchronous Mips Processors: Educational Simulations, Robert L. Webb

Master's Theses

The system clock has been omnipresent in most mainstream chip designs. While simplifying many design problems the clock has caused the problems of clock skew, high power consumption, electromagnetic interference, and worst-case performance. In recent years, as the timing constraints of synchronous designs have been squeezed ever tighter, the efficiencies of asynchronous designs have become more attractive. By removing the clock, these issues can be mitigated. How- ever, asynchronous designs are generally more complex and difficult to debug. In this paper I discuss the advantages of asynchronous processors and the specifics of some asynchronous designs, outline the roadblocks to asynchronous …


Class-F Power Amplifier With Maximized Pae, Kai Shing Tsang Aug 2010

Class-F Power Amplifier With Maximized Pae, Kai Shing Tsang

Master's Theses

Due to the rapid development of telecommunication devices, operating speeds are getting faster and more power is being consumed by those devices. Therefore, there is a big concern on how to prolong the battery life in order to fit consumers’ needs. Power amplifiers (PA) at the front end of wireless equipment have drawn a big concern from engineers because of their large power consumption in the system. There is a lot research conducted on PA solutions for improving power-added efficiency (PAE) of amplifiers. PAE is a figure of merit representing how efficient the PA converts DC power to RF power. …


Enhanced Cal Poly Super System Simulink Model, Matthew Ogden Mcfarland Aug 2010

Enhanced Cal Poly Super System Simulink Model, Matthew Ogden Mcfarland

Master's Theses

The Cal Poly Sustainable Power for Electrical Resources (SuPER) project is a solar power DC distribution system designed to autonomously manage and supply the energy needs of a single family off-the-grid home. The following thesis describes the improvement and re-design of a MATLAB Simulink model for the Cal Poly SuPER system. This model includes a photovoltaic (PV) array, a lead-acid gel battery with temperature effects, a wind turbine model, a re-designed DC-DC converter, a DC microgrid, and multiple loads. This thesis will also include several control algorithms such as a temperature controlled thermoelectric (T.E.) cooler, intelligent load switching, and an …


Irrigation Leak Detection: Using Flow Rate Sensors To Detect Breaks In An Irrigation System, Adam Openshaw, Kalvin Vu Jun 2010

Irrigation Leak Detection: Using Flow Rate Sensors To Detect Breaks In An Irrigation System, Adam Openshaw, Kalvin Vu

Computer Engineering

This report details the exploration and invention of a mechanism that can detect breaks in an irrigation system. With the ultimate goal of conserving water, we have designed an inexpensive, self sustaining flow rate monitor that can be used to identify anomalies in an irrigation system and wirelessly communicate the status of the system to a base station. Our implementation can also determine the direction of the anomaly based on the nature of the anomaly itself. This means that multiple monitors can be used to pinpoint the location of a break within the system in addition to merely detecting its …


The Applications And Limitations Of Printable Batteries, Matthew Delmanowski Jun 2010

The Applications And Limitations Of Printable Batteries, Matthew Delmanowski

Graphic Communication

This study focuses on the potential applications for printed batteries and how they could affect the printing industry. It also analyzes the main problems associated with manufacturing this technology and what needs to be done to overcome these issues. To find the answers to these questions, two methods of research were used. The first was through the elite and specialized interviewing of Dr. Scott Williams of Rochester Institute of Technology and Professor Nancy Cullins from Cal Poly. The second form of research was a common, yet useful, method called secondary research. This entailed looking at recent written research papers about …


Systems Engineering Analysis And Digital Communication Bus Design For The Cal Poly Super Project, Matt Marcus Camack Jun 2010

Systems Engineering Analysis And Digital Communication Bus Design For The Cal Poly Super Project, Matt Marcus Camack

Master's Theses

With an expected lifetime of 20 years and an expected cost of $500, the Cal Poly Sustainable Power for Electrical Resources (SuPER) project needed a strong central design. This thesis looks at the work completed by students over the previous 5 years, with an eye on the future, to create the phase 2 design. Part of this new structure focuses on a distributed communication bus for monitoring system health and status. Instead of complex and costly computer or FPGA systems, the new system will run solely with microcontrollers. This reduces costs and will hopefully still be used within 5, 10, …


Pulse Density Modulated Soft Switching Cycloconverter, Jesse Timothy Adamson Jun 2010

Pulse Density Modulated Soft Switching Cycloconverter, Jesse Timothy Adamson

Master's Theses

Single stage cycloconverters generally incorporate hard switching at turn on and soft switching at turn off. This hard switching at turn on combined with the slow switching speeds of thyristors (the switch of choice for standard cycloconverters) limits their use to lower frequency applications.

This thesis explores the analysis and design of a pulse density modulated (PDM), soft switching cycloconverter. Unlike standard cycloconverters, the controller in this converter does not adjust thyristor firing angles. It lets only complete half cycles of the input waveform through to the output. This allows and requires a much greater frequency step down from the …


Modular Laser Combat System For Remotely Operated Vehicles: Bridging The Gap Between Computer Simulation And Live Fire, Thomas Edward Fulenwider Jun 2010

Modular Laser Combat System For Remotely Operated Vehicles: Bridging The Gap Between Computer Simulation And Live Fire, Thomas Edward Fulenwider

Master's Theses

In the emerging industry of small unmanned vehicles, pioneered by small businesses and research institutions, a suitable combat system test platform is needed. Computer simulations are useful, but do not provide the definitive proof of effective operation necessary for deployment of a combat system. What is needed is an affordable simulated weapons system that enables live flight testing without the used of live weaponry.

A framework is developed here for the construction of a simulated weapon using Free Space Optical (FSO) infrared communication. It is developed in such a way to ensure compatibility with a variety of platforms including ground …


Analog Electric Guitar Distortion Effects And Headphone Amplification, Michael Alexander Jenkins Jun 2010

Analog Electric Guitar Distortion Effects And Headphone Amplification, Michael Alexander Jenkins

Electrical Engineering

The goal of this project was to create an electronic system which integrates popular audio processing effects as well as headphone amplification circuitry for use with an electric guitar. By implementing a system which fits natively inside the body of an electric guitar, the need for numerous external accessories relating to a standalone amplifier system is eliminated, improving device versatility and portability.


Electric Bicycle System, Robert Cong, Rodney Martinez, Mark Casilang, Peter Vong Jun 2010

Electric Bicycle System, Robert Cong, Rodney Martinez, Mark Casilang, Peter Vong

Electrical Engineering

The Electric Bicycle System is a systems project that incorporates three different ways of charging a lithium-ion battery: the 120VAC wall outlet, regenerative braking, and solar power; which is used to power an electric hub motor running a bicycle. The purpose of the project is to show that it is possible and relatively simple, to build an electric bicycle by oneself. This project can be broken down into five separate categories: the lithium-ion battery, the DC-DC boost converter, the solar panel, the motor, and the motor controller. Each of these will be built upon and improved further by future students, …