Engineering Commons^™

High Voltage Pulse-Width Generator For The Algae Biofuel Project, Philip Yu, Stephen Leung

Electrical Engineering

This purpose of this project, sponsored by Boeing and advised by Dr. Arakaki and Dr. Taufik, is to build a high voltage pulse width generator that lyses algae cells to harvest the biofuel within. This project uses Emmanuel Loza's thesis on a cascaded high voltage converter with variable control to build a portable pulse width generator with independent control on the peak voltage, pulse width, and frequency. The project focuses on creating a pulse width generator capable of finding the most optimal pulsed electric field to lyse algae. The pulse width module ranges from 10V-80V peak voltage, 60Hz-100 kHz frequency, …

Transimpedance Amplifier For Polymer Photodiodes, Sheridan Knighton

Electrical Engineering

Dr. Braun’s students in the Polymer Electronics Lab currently have a way to measure the light intensity from their light emitting devices however it consumes an unnecessary amount of space and power. I offer to improve upon the existing transimpedance circuit that Dr. Braun currently uses, reducing the total space occupied by the circuit and the power consumption of the current setup. The transimpedance circuit measures the incidence light intensity from the polymer-based photo detector and outputs an accurate, discrete, and measurable voltage. The current setup however utilizes two 20V wall warts for the positive and negative rails of the …

Energy Harvesting From Exercise Machines: Lt8705 Dc-Dc Conversion For Elliptical Trainers, Braden Burk, Raj Bhula, Nathan Mckay

Electrical Engineering

Cal Poly’s Energy Harvesting from Exercise Machines (EHFEM) program aims to power the grid using human energy harvested from exercise machines in its gym. Doing so could save the school money and increase the total supply of power available on the grid. This document belongs to one of many groups attempting to design a suitable DC-DC conversion system for an elliptical trainer using an LT8705 Four-Switch Buck-Boost converter. Past teams have built other converters and developed system compatibility characteristics such as filtering, safety, and stability for interfacing components. These teams fall into one of two departments in EHFEM: DC-DC Conversion …

Microprocessor Management Of Energy Harvesting Buck Boost Converters, Timothy O'Sullivan

Electrical Engineering

No abstract provided.

Buck Converter, Bowen Liu

Electrical Engineering

The recent sustainable energy growth triggered a huge power electronics demand, specifically related to power conversion. My senior project is a design of a buck converter which steps down the voltage from photovoltaic cells ranging from 5 to 40V to a rechargeable battery with 5V. This converter has a high enough power efficiency to effectively convert the energy harnessed from PV panels.

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 …

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 …

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.

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 …

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 …

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 …

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 …

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.

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 …

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 …

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 …

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 …

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 …

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 …

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. …

Singing Arc, Justin Kis

Electrical Engineering

This project aims to develop a singing arc. A singing arc is commonly, though mistakenly, referred to as a plasma speaker. Whereas a traditional speaker uses a pulse width modulated (PWM) signal to move an electromagnet, which in turn moves a cone, which generates sound waves, the singing arc sends a PWM signal through a standing spark, which vibrates, which generates sound waves.

Several plans for the singing arc are readily available online. This project will analyze the similarities between a selection of them, try to eliminate any faults in design, and improve the function of the circuit. The final …

The Garage Band Lightshow, Jason Descenzo

Electrical Engineering

The expenses musicians accrue make it hard to afford all the different equipment needed to perform and very unlikely that the average start up band or artist can afford the luxury of a musical light show in their early performances. The Garage Band Lightshow provides an easily set up and affordable way for musicians to use concert lighting in their performances. The Garage Band Lightshow provides one LED box. The light box responds to an audio signal and provides varying pulses and colors of light depending on the high, mid, and low frequencies of the audio signal. The Garage Band …