Electrical and Electronics Commons^™

Improvements To A Bi-Directional Flyback Dc-Dc Converter For Battery System Of The Dc House Project, Michael Wu

Master's Theses

The DC House project relies primarily on renewable energy sources to provide DC power to the various loads of the house. However, not all renewable sources are capable of providing power at all times of the day. A back-up energy source in the form of a battery storage system must be available to meet the electrical needs of the house. A bi-directional flyback power converter was initially designed to allow a battery to charge from as well as discharge to the 48V bus line of the DC House. The design provided a 35W prototype to demonstrate the converter’s feasibility. Further …

Ac Power Combining Strategy With Application To Efficient Linear Power Amplifiers, Rudi Matthew Bendig

Master's Theses

With the ongoing push for wireless systems to accommodate more users and support higher data rates more efficient modulation schemes have been created that are more advanced than simple FM and AM modulation used for radio broadcasting. These modulation schemes, such as orthogonal frequency division multiplexing (OFDM), suffer from high peak to average power ratios. Standard Class A and Class AB amplifiers cannot simultaneously achieve good linearity and efficiency, and therefore there has been an increase in the development of new topologies to combat this issue. Common features to these circuits is power combining of two or more separate transistors. …

Variable Precision Tandem Analog-To-Digital Converter (Adc), Colton A. Parsons

Master's Theses

This paper describes an analog-to-digital signal converter which varies its precision as a function of input slew rate (maximum signal rate of change), in order to best follow the input in real time. It uses Flash and Successive Approximation (SAR) conversion techniques in sequence.

As part of the design, the concept of "total real-time optimization" is explored, where any delay at all is treated as an error (Error = Delay * Signal Slew Rate). This error metric is proposed for use in digital control systems. The ADC uses a 4-bit Flash converter in tandem with SAR logic that has variable …

Mos Current Mode Logic (Mcml) Analysis For Quiet Digital Circuitry And Creation Of A Standard Cell Library For Reducing The Development Time Of Mixed Signal Chips, David Marusiak

Master's Theses

Many modern digital systems use forms of CMOS logical implementation due to the straight forward design nature of CMOS logic and minimal device area since CMOS uses fewer transistors than other logic families. To achieve high-performance requirements in mixed-signal chip development and quiet, noiseless circuitry, this thesis provides an alternative toCMOSin the form of MOS Current Mode Logic (MCML). MCML dissipates constant current and does not produce noise during value changing in a circuit CMOS circuits do. CMOS logical networks switch during clock ticks and with every device switching, noise is created on the supply and ground to deal with …

St. Jude Medical - R&D Robot For Sensor Testing, Andrew Chanul Kim, Stanley Logan Laszczyk, Edgar Nava, Nathan Gall

Electrical Engineering

No abstract provided.

Rapid Battery Exchange Safety And Sensing, Ben John Froelich, Isaac Sungjin Kim

Electrical Engineering

The Rapid Battery Exchange system (RBX) swaps batteries in an electric van, allowing almost continuous operation of the vehicle. The RBX system is designed and built by The Cal Poly Electric Vehicle Engineering Club (EVEC). The system includes the exchange ramp, two battery packs, and the electric “G-Van.” While the vehicle drives using one of the battery packs, the other pack charges in the exchange ramp. When the van’s battery depletes, it drives onto the ramp and swaps the dead battery for the charged one, and the process repeats.

The RBX battery pack safety and sensing project divides into two …

Battery Management System, Michael Desando, Kyle Woody

Electrical Engineering

Problem Statement:

There have been recent reports of multi-million dollar companies having to recall entire projects due to their BMS’s malfunctioning or operating incorrectly. The purpose of this project is to analyze the future of batteries, the Lithium-Ion cell, and to exercise a BMS to better understand its capabilities and possible cases for errors. Lithium ion batteries are intolerant of overcharge and overdischarge. Abuse of this kind can result in high temperatures, venting of gases, fire, or explosion. Therefore battery management systems have been devised to prevent such abuse. Recent events such as fires on the Boeing Dreamliner and the …

Low Voltage Cmos Sar Adc Design, Ryan Hunt

Electrical Engineering

This project centers on the design of a single ended 10-bit successive approximation register analog to digital converter (SAR ADC for short) that easily interfaces to a micro-controller, such as an Arduino. With micro-controller interfacing in mind, the universal data transfer technique of SPI proved an easy way to communicate between the ADC and the micro-controller. The ADC has a range of 1V (highest code value) to 0V (lowest code value) and operates from a single voltage rail value of 1.8V. Typical SPI clock speeds run on the order of 2MHz and with a 10-bit ADC this means a sampling …

Analog Violin Audio Synthesizer, Brandon E. Davis

Electrical Engineering

Abstract In the past decade, music electronics have almost completely shifted from analog to digital technology. Digital keyboards and effects provide more sound capabilities than their analog predecessors, while also reducing size and cost. However, many musicians still prefer analog instruments due to the perception that they produce superior sound quality. Many musicians spend extra money and accommodate the extra space required for analog technologies instead of digital.

Furthermore, audio synthesizers are commonly controlled with the standard piano keyboard interface. Many musicians can perform sufficiently on a keyboard, but requiring a specific skill set limits the size of the market …

Buck-Boost Dc-Dc Converter With Input Protection System For The Energy Harvesting From Exercise Machines Project, Byungjae David Yoo, Sheldon Tyler Kong Ming Chu

Electrical Engineering

Cal Poly’s Energy Harvesting from Exercise Machines (EHFEM) project comprises of multiple subprojects seeking to effectively create a sustainable energy source through harvesting electrical energy generated from physical exercise machines. This project designs and implements a Buck-Boost DC-DC converter using a LT3791-1 4-Switch Buck-Boost Controller, replacing the previous SEPIC design. The DC-DC converter must operate within limits set by the maximum input range of the LT3791-1 controller. An input protection system prevents inputs higher than rated values, which may adversely damage the Buck-Boost DC-DC converter. These inputs include overvoltage transients, average voltage, and current output by the Precor EFX 561i …

Real Time Swim Instructor, Konrad Antoniuk

Electrical Engineering

Both competitive and recreational swimmers want an efficient swim stroke but often lack consistent feedback with technical insight. Competitive swimmers rely on coaches for instruction but have to stop swimming to listen. The Real Time Swim Instructor project provides live feedback to a swimmer so they can feel their stroke correction while they’re swimming. The developing swimmer feels the difference between correct and incorrect form instantaneously.

The project takes on the responsibility of measuring the moving body, accurately determining stroke improvement, functioning under water, and providing recognizable feedback. Additionally, the user can review their swim from data stored in memory. …

Mobile Solar Pv Trainer, Matthew Myers, Matthew Clause, Lawrence Smith

Mechanical Engineering

The aim of the Mobile Solar PV Trainer Project was to design, construct and test a versatile and robust laboratory training rig for the Cal Poly Electrical Engineering department. This project was inspired by the desire of one or more California Polytechnic State University electrical engineering professors to add laboratory components to two established upper division electrical engineering courses in photovoltaic panels and solar power. This report contains a detailed description of the trainer’s desired specifications, our ideation process, a thorough description of the selected trainer design including part drawings, assembly documentation and a bill of materials as well as …

Portable Nano Hydro Generator For The Dc House Project, Caleb David Fink, Victor Olusoji Ojewole, Christopher Mapua Tan

Electrical Engineering

This Senior Project entails the design and testing processes of the Portable Nano Hydro Generator for the continuing DC House Project. No natural resources should go unused, especially in developing countries where they are found in abundance. Small streams in particular have potential to further Professor Taufik's DC House Project that will provide electricity to 1.6 billion people in the world without access to electricity upon completion. The goal of this project is to create a small portable generator that utilizes the discharge from small streams and convert it into useable electricity that could charge a car battery as an …

Protection System For The Energy Harvesting From Exercise Machines (Ehfem) Project, Eric Funsten, Cameron Kiddoo

Electrical Engineering

The goal of the Energy Harvesting from Exercise Machines (EHFEM) project seeks to harness the energy generated by people using exercise machines and deliver this energy to the electric grid [1]. The implementation consists of a protection system, DC-DC converter, and an inverter. This project involves redesigning the existing DC-DC input protection circuit and current limiter for the EHFEM project [2]. The DC-DC converter takes in the power from the exercise machines and converts it to a manageable voltage level for the inverter. Due to a problem where the inverter may overload the converter, a current limiter sets to limit …

Bike Safe: An Automatic Turn Signal System, Betty He Chan, Ricardo Alberto Duran

Electrical Engineering

Bicycles are vehicles that do not require a license to operate and share the road with cars, motorcycles, and other fast moving vehicles. An improper lane change from a bicyclist, such as one without any warning, can lead to great injury or death (especially after sundown). Bike Safe addresses this safety concern by providing a low-cost device that mimics the warning system motorists’ use every day. The system consists of a red brake light and amber turning signal lights that mounts to the rear of the bike, as well as a white headlamp that mounts to the front handlebars. The …

All Purpose Mobile Gps, James C. Smith, Matt Weege, Kevin Peters

Electrical Engineering

The aim of the All Purpose Mobile GPS (The System) is to create a GPS tracking device that can accurately record location and calculate velocity, distance traveled and elevation change even when the satellite signal is lost. This data can later overlay on existing internet-based maps illustrating a trip to oneself or others. The portable tracker consumes very little power achieving several days’ worth of power in a single charge. A solar cell provides a quick battery boost in a pinch. SD Card storage increases compatibility with computers and other forms of data transfer. Data processing, such as viewing the …

Smart Weights, Luke W. Rafla-Yuan, Austin C. Fox

Electrical Engineering

The goal of this project is to design and implement weights which can record and analyze work out patterns. Motivation for this project stems from the high cost of personal training. The hope is that this device will provide many of the benefits a user receives from personal training at only a fraction of the cost. The Smart Weight is designed with an on-board Inertial Measurement Unit providing acceleration, gyroscope, and magnetometer data. A microcontroller records and analyzes changes in motion, feeding this data into Multiplicative Recurrent Neural Network (MRNN) for exercise classification. A Raspberry Pi was chosen as the …

Design Improvement For The Smart Dc Wall Plug, Cory Yee, Haoyan Huang

Electrical Engineering

The DC smart wall plug is a subsystem within the Cal Poly DC House Project. The previous version faces challenges supplying DC voltage to meet household appliances’ nominal values. Specifically, it can only output the minimum required voltage for DC appliances to operate, resulting in unwanted power loss. In addition, the maximum output voltage is rated at 15V, which is insufficient to power most DC appliances. This design improvement project incorporates NFC technology as a solution to overcome the power loss and a new buck converter configuration to increase the output voltage range. Additionally, the new design introduces short-circuit and …

Team Omnimouse, Derek J. Halman, Josh B. Porter, Steven A. Silver, Ian S. Stemper

Computer Engineering

INFORMATION, DATA, FIGURES AND DRAWINGS EMBODIED IN THIS DOCUMENT ARE STRICTLY CONFIDENTIAL AND ARE SUPPLIED ON THE UNDERSTANDING THAT THEY WILL NOT BE DISCLOSED TO THIRD PARTIES WITHOUT THE PRIOR WRITTEN CONSENT OF QUALITY OF LIFE PLUS.

Sonar For The Visually Impaired, Anastasia Newark, Edwin Ng, Scott Terhorst

Biomedical Engineering

There are currently no inexpensive assistive devices that allow the visually impaired detect low hanging objects that are above waist height and may cause injury, such as a rope or tree branch. The challenge presented to the team by the Quality of Life Plus Lab (QL+) was to develop a Sonar Cane device that attaches to a traditional white cane to address this problem. This device must be lightweight, inexpensive to manufacture, have a long battery life, and accurately detect obstacles to prevent user injury.

3-Input Pre-Amp, Daniel Pico, Carla Salome Ramirez

Electrical Engineering

There is no commercial available pre-amplifier that takes 3 individual input signals and synthesizes them for an acoustic guitar. The acoustic pre-amplifier takes three separate small signal inputs and combines or isolates to endure amplification depending with user setting. The user deciphers which signal or signal combination is desired. The device features coil pick-up, microphone pick-up, and piezo disc pick-up for variety of tone quality and control.

Bipolar Pulse Width Modulation Inverter, Xin Chen, Ryan Harada

Electrical Engineering

The project entails the design of an improved PWM inverter circuit for the inverter lab experiment in the introductory power electronic course. The improved PWM inverter uses bipolar switching with a half bridge control circuit. The inverter utilizes two ICL8038 chip to generate both the control and carrier signals. The improved inverter enhances the system's portability, protection and is easy to understand from the prior design. The improved PWM inverter provides AC variable single phase 65 Hz AC output voltage from DC input signal. The finished product will be used specifically in the EE 410 laboratory course.

Rapid Battery Exchange (Rbx) Charger Interface, Adam Morris

Electrical Engineering

As fossil fuel prices steadily rise and concerns associated with burning the fuels increase, electric vehicle sales continue to grow. According to the U.S. Department of Energy, EV sales “tripled from about 17,000 in 2011 to about 52,000 in 2012” [1]. In order to meet consumer transportation expectations—molded by fuel-powered vehicles—electric cars must have the ability to “refuel” quickly. Rapidly charging an EV’s traction battery poses one solution but doing so requires large power levels “five times as much as the average office consumes,” [2] making rapid charging less than ideal for the masses. Alternatively, swapping an EV’s depleted battery …

Integration Of Pv & Simulated Dc Sources For The Dc House, Arvind Ramesh, Kevin Gingrich, Scott Chau

Electrical Engineering

The DC House, an ever improving project, uses only pure DC power which most renewable energy sources generate, from solar to wind power. The DC House and this project expect a donation of photovoltaic modules to supply a constant source of DC power. At the moment, the DC House desperately needs power sources because not only does the house have various loads unaccounted for, but the distribution system to determine proper power flow needs a redesign. The project chose to account for these issues by implementing a solar panel onto the DC House and a power distribution module to have …

Low Temperature Battery Monitoring And Control System – Lithium-Ion Low Temperature Case Study, Aaron Lee, Richard Tham, Ken Huynh

Electrical Engineering

This open-ended research project, co-advised by Dr. Prodanov and Dr. Dolan, studies electronic and battery failures at low temperatures (between -70 ºC to 0 ºC). The main battery technology used for this project is Lithium-ion. The research project consists of two systems: the monitoring system and the actuating system. This project accomplishes the first part and assesses the feasibility of measuring the internal impedances of batteries for low-Earth-orbit (LEO) satellites as a means to monitor battery health. It also monitors the effects caused by low temperature conditions through internal impedance measurements from 0 ºC through -70 °C. It includes designing …

Clear Circuit Contact Lens, Paul Hecker Ii, Phillip Azar, Alexander Do, Benny Ng, Errol Leon

Electrical Engineering

The clear active contact lens project aims to address safety and hazard awareness with an unexplored field of eye wear technology. With advancements in nanotechnology and the advent of circuits on contact lens, this project is one of the first research and development into this new field, following University of Washington and Google. The team focuses on the safety and biocompatibility of the contact lens for a comfortable ease of use. The designs push the limits of thin film printed technology with its pursuit of fine designs of 250μm antennas. The project streamlines the manufacturing process for a combination substrate …

Rubidium-Based Atomic Clock, Kate Miles

Physics

In this paper we will explore the process of building an atomic clock from a function generator, go into an in-depth introductory discussion of the Datum LPRO, and examine how rubidium function generators work.

Alternate Computer Input Device For Individuals With Quadriplegia, Tobais Elder, Michelle Martinez, David Sylvester

Biomedical Engineering

This project details the design development of an alternative computer input system that allows a person with quadriplegia to move a computer's cursor and activate left and right click button inputs. After researching and analyzing possible solutions, an end design was chosen that most appropriately satisfied all user requirements and engineering specifications. This final design employs a head mounted Inertial Measurement Unit (IMU) with 9 DoF (Degrees of Freedom) to track head movements and correlate these motions to computer cursor movements. A Sip-Puff Transducer monitors and interprets a user's application of negative and positive air pressure differentials to a vinyl …

Global Optimization Methods For Localization In Compressive Sensing, Marco Rossi

Dissertations

The dissertation discusses compressive sensing and its applications to localization in multiple-input multiple-output (MIMO) radars. Compressive sensing is a paradigm at the intersection between signal processing and optimization. It advocates the sensing of “sparse” signals (i.e., represented using just a few terms from a basis expansion) by using a sampling rate much lower than that required by the Nyquist-Shannon sampling theorem (i.e., twice the highest frequency present in the signal of interest). Low-rate sampling reduces implementation’s constraints and translates into cost savings due to fewer measurements required. This is particularly true in localization applications when the number of measurements is …

Congestion Control, Energy Efficiency And Virtual Machine Placement For Data Centers, Yan Zhang

Dissertations

Data centers, facilities with communications network equipment and servers for data processing and/or storage, are prevalent and essential to provide a myriad of services and applications for various private, non-profit, and government systems, and they also form the foundation of cloud computing, which is transforming the technological landscape of the Internet. With rapid deployment of modern high-speed low-latency large-scale data centers, many issues have emerged in data centers, such as data center architecture design, congestion control, energy efficiency, virtual machine placement, and load balancing.

The objective of this thesis is multi-fold. First, an enhanced Quantized Congestion Notification (QCN) congestion notification …