Engineering Commons^™

Wirelessly Controlled Smart Outlet, Andrew Godsil, Ariel Dubinsky

Electrical Engineering

Popularity of home automation devices has increased greatly in recent years due to higher affordability and simplicity through smartphone and tablet connectivity. For the purpose of this experiment, we have developed the Smart Outlet: a stand-alone communication unit, used to connect home outlets to the internet. The Smart Outlet controls lighting and simple appliances throughout the home, remotely, using wireless commands from the web. A Google Calendar interface directly controls the outlets’ function by scheduling them with dedicated calendar events. The calendar’s interface can even be accessed from multiple different platforms (i.e. phones, computers, tablets) for the convenience of all …

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.

Power Chest Strap, Adrianne Thoroddsson, Dennis Lin

Electrical Engineering

The Power Chest Strap is an unobtrusive device, like a heart rate monitor, worn around the chest that harvests energy from the expansion of the chest during breathing. The chest strap stores electrical energy that can charge electronic devices such as cell phones. Since small portable devices grow in number, the power strap allows a convenient way to charge your device without having to find a wall outlet for a charger. Research on systems that scavenge energy from arm or leg movement already exist, but these systems require the ability of the user to move their arms and legs. The …

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 …

Study Of Grating Layer Location Of A Gan Nano-Grated Led And Comparison Of Triangular And Squared Ito Nano-Grating Of Gan Leds, Ashli Lauren Behill

Electrical Engineering

Reducing energy consumption is one the most critical and necessary actions being continually worked towards by many. According to the U.S. department of Energy, solid-state lighting (SSL) has the potential to reduce the light consumption in the United States by nearly one half and that light-emitting diodes (LEDs) will change the way of lighting in our homes and businesses. Gallium Nitride (GaN) based light emitting diode (LED) technologies are continuing to have a fast growing contribution to various applications in today’s society. GaN LEDS are already replacing the esteemed incandescent light bulb, and are transforming traffic lighting, optical interconnects, backlight …

Merry-Go-Round Human Powered Generator, Sarah Lorraine Ashe, Salvador Navarro

Electrical Engineering

How do you bring electricity to families who have limited resources in a developing country? The DC House project, advised by Dr. Taufik, provides a way for kids to have fun, exercise and generate power for their homes – play-park human powered generators. This project intends to create a more efficient and cost effective way for playground equipment to be implemented for power generation. The redesigned and reconstructed merry-go-round human powered generator converts mechanical energy into electrical energy to power the DC house. This was a fully functioning generator that needed a better voltage gain, as well as, a more …

Human-Powered Swing Generator, Danny Cai, Timothy Lai, Brandon Wong

Electrical Engineering

Many developing countries lack sufficient resources to provide enough electricity for every family to live with a satisfying level of comfort and convenience. Our project proposes a solution that provides families with an alternative access to electricity using a playground swing. This project addresses the design and construction of the Human-Powered Swing Generator, which converts mechanical energy to electrical energy for charging a battery. The charged battery serves as a source of DC energy for potential DC purposes, such as charging a cell phone.

Rfid Door Lock, Ralph Ting, Mackenzie Keane

Electrical Engineering

The RFID Door Lock is a lock that is simple to install and allows the user to easily lock and unlock doors. It will contain a RFID reader/writer and a magnetic door lock for simple use. All the user will need is an RFID tag to be able to unlock and lock the door. A LED will be used to let the user know when the door is in fact locked. The components included in the module are small and compact. Additionally, the door lock is simple and easy to install. It does not require the consumer to disassemble 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 …

Piezoelectric Powered Led Street Reflector, Collin Shane Douglass

Electrical Engineering

In many areas of Washington, it rains for a majority of the year. During rainy weather it becomes difficult to see street lanes and dividers, causing hazardous road conditions. The Piezoelectric Powered LED Street Reflector solves this problem. The PPL Street Reflector modifies a street reflector with LED lights. These lights help drivers clearly see where dividers and street lines are in non-ideal weather conditions, such as rain, fog, and snow. The PPL Street Reflector capabilities include harvesting energy through the Piezoelectric Effect, creating a self-sustaining device with minimal maintenance.

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 …

Automated Pet Food Dispenser, Kevin M. Shibley

Electrical Engineering

Electronics revolutionize the world and simplify life. The Automated Pet Food Dispenser (APFD) revolutionizes the pet industry and provides unprecedented food capacity and delivery capability, giving pet owners worry-free vacationing. Sensors and timers optimize functionality and reduce waste while improving reliability and usability. User-defined settings and customization gives the device adaptability to meet every customer’s needs.

Energy Harvesting From Exercise Machines - Dc-Dc Buck Boost Converter (Lt3791), Matthew B. Wong

Electrical Engineering

Cal Poly’s ongoing Energy Harvesting From Exercise Machines (EHFEM) project proposes sustainability and energy saving costs through modifying exercise machines generating DC power, providing a renewable energy resource through physical exercise. The EHFEM project contains multiple sub-projects involving modifying several different exercise machines. Each machine generates DC power and an inverter converts this power to AC. This AC power returns to the grid. This project addresses an issue involving a previously installed DC-DC converter not returning power properly. When generating DC power, the grid demands a specific AC voltage, but the generated power through the previous DC-DC converter and power …

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 …

Fpga Based Bitcoin Mining, Philip Dotemoto

Electrical Engineering

This project attempts to implement an open source FPGA based Bitcoin miner on an Altera DE2-115 development board. Bitcoin is an experimental peer-to-peer digital currency based on public key cryptography. The advantages of Bitcoins are that they can be transferred between any two people anywhere in the world, and they do not have the same fees and lack of control associated with traditional methods of currency transfers. The first part of this project focuses on detailing how the Bitcoin network and open source miner work. The second part of the project attempts to improve the performance of the open source …

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.

Wideband Balun Design With Ferrite Cores, Paul R. Biggins

Electrical Engineering

This project explores different balun devices in order to develop a balanced to unbalanced transformer that will operate over a wide bandwidth. The balun must operate from at least 1 MHz (or below) to the highest possible frequency. It must have an insertion loss of less than 1 dB under the ideal case with an imbalance of less than 1 dB and 2.5 degrees. Three balun topologies were tested, each built for a 1:1 impedance transformation ratio. Techniques of measuring each balun topology were investigated including gathering accurate data from a three port device with two port instruments and measuring …

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 …