Electrical and Electronics Commons^™

Developing Positive Thermal Coefficient (Ptc) Heaters For Solar Electric Cooking, Katarina Ivana Brekalo, Andrew Shepherd

Physics

Positive Thermal Coefficients, PTCs, are materials that abruptly change in resistance in response to changes in temperature. The purpose of this experiment is to explore the viability of using the switching type ceramic PTC thermistor as a replacement for current resistive heaters. These types of PTCs have a nonlinear change in resistance with increases in temperature. This device will be used as a temperature-controlling heating element intended to power an Insulated Solar Electric Cooker (ISEC). The ISEC is designed to cook meals throughout the day for impacted communities as an alternative cooking method that doesn’t require biofuel as an energy …

An Inexpensive Maximum Power Point Tracking System For An Insulated Solar Electric Cooker Using An Off-The-Shelf Buck Converter, Andrew A. Perez

Physics

A specialized control circuit using an off-the-shelf buck converter is built for an Insulated Solar Electric Cooker (ISEC). Cost and efficient power delivery are the focus. An ISEC is synonymous to a direct load heat resistor, allowing a specific maximum power point tracking (MPPT) algorithm and fewer components. Only a microcontroller, voltage sensor, and digital-to-analog converter are used with the buck converter to maximize the power delivered by a 100W solar panel for the 3.3Ω load.

Design And Analysis Of A Discrete, Pcb-Level Low-Power, Microwave Cross-Coupled Differential Lc Voltage-Controlled Oscillator, Pavin Singh Virdee

Master's Theses

Radio Frequency (RF) and Microwave devices are typically implemented in Integrated Circuit (IC) form to minimize parasitics, increase precision and tolerances, and minimize size. Although IC fabrication for students and independent engineers is cost-prohibitive, an abundance of low-cost, easily accessible printed circuit board (PCB) and electronic component manufacturers allows affordable PCB fabrication.

While nearly all microwave voltage-controlled oscillator (VCO) designs are IC-based, this study presents a discrete PCB-level cross-coupled, differential LC VCO to demonstrate this more affordable and accessible approach. This thesis presents a 65 mW, discrete component VCO PCB with industry-comparable RF performance. A phase noise of -103.7 dBc/Hz …

Sunsation’S Solar Powered Picnic Table, Michelle M. Barnett, Christopher Barber, Casey Durham, David Mason

Mechanical Engineering

Team SunSation is an interdisciplinary senior design project group that was tasked with developing a semi-permanent seating area for Cal Poly's electrical engineering courtyard. The EE courtyard is populated with plastic folding tables and chairs that are slowly falling apart. Dale Dolan, the head of the EE department, requested that a table design be developed that incorporates the use of solar panels. The addition of the solar panels to the table would help promote clean renewable energy as well as provide shade to those sitting in the courtyard.

The solution that SunSation arrived at is broken up into mechanical/structural, electrical, …

8 Dof Quadrupedal Hopping Robot, Clayton T. Elwell, John Bennett, Tyler Mccue, Daniel Munic

Mechanical Engineering

The goal of our senior project was to fabricate an eight degree of freedom (DOF) prototypical quadrupedal robot, develop a controller than commands the quadruped to repeatedly jump 10 cm in the air, and fabricate a modular test stand to safely deploy our controller on the quadruped. The creation of a functional quadruped will bring attention to Dr. Siyuan Xing and Charlie Refvem’s research group, Cal Poly Legged Robots, and will give future Cal Poly undergraduate and graduate students a learning tool to explore dynamic control of biomimetic robotic systems.

Over the course of our senior project, we successfully manufactured …

Dual-Axis Precision Imager, Gary Huarng

Computer Engineering

The Dual-Axis Precision Imager (DAPI) is a drawing robot that processes images and draws them on a whiteboard. The system has two modes: a Sobel filter mode that finds the edges of the input image with a Sobel filter, and a tri-tone grayscale mode that approximates the shading of the input image with the colors white, gray, and black. The DAPI consists of an Arduino-controlled XY gantry system with a pen mounted on the gantry head, and a Processing IDE program that processes the original image, converts the processed image into gantry instructions, and sends them to the Arduino for …

Current-Source Dc-Dc Converter For Fiber-Optic Communication Systems, Jissell C. Jose

Master's Theses

In this thesis, a proof of concept for a current-source DC-DC converter for powering sensors used in an underwater communications system is presented. The proposed converter steps down an input current of 0.9 A to 0.625 A, while maintaining an output voltage of 24 V and output power of 15 W. The complete steady-state analysis and design of the proposed converter in its single-stage form is also explained in detail. Performance evaluation of the proposed converter was carried out using LTspice. Results of the simulation demonstrate that the design was able to produce average output current of 0.639 A at …

A Nano-Drone Safety Architecture, Connor J. Sexton

Master's Theses

As small-form factor drones grow more intelligent, they increasingly require more sophisticated capabilities to record sensor data and system state, ensuring safe and improved operation. Already regulations for black boxes, electronic data recorders (EDRs), for determining liabilities and improving the safety of large-form factor autonomous vehicles are becoming established. Conventional techniques use hardened memory storage units that conserve all sensor (visual) and system operational state; and N-way redundant models for detecting uncertainty in system operation. For small-form factor drones, which are highly limited by weight, power, and computational resources, these techniques become increasingly prohibitive. In this paper, we propose a …

Smart Usb-C Wall Plug For The Dc House Project, Ridge Lahti, Dino Maslic

Electrical Engineering

DC operated devices and appliances powered by AC systems suffer inefficiencies resulting from the losses of converting AC energy into DC energy. At Cal Poly, the DC House Project aims to minimize the need for AC electricity in homes and encourage the use of renewable energy systems. The DC House uses a 48V DC bus that must be stepped down for use with increasing number of DC loads in a typical home. In this project, a Smart USB-C Wall Plug is designed to work with USB Power Delivery to provide a variable voltage output for use with these DC loads …

Hvac Hardware Modeling Using Programmable Automatic Controller, Panthil Ketan Patel, Lumanti Tuladhar

Electrical Engineering

The primary purpose of this project is to use the donated programmable logic controllers (PLC) from Schneider Electric to develop experiments for a future lab class at Cal Poly. Our goal as the first group working on this project is to develop an experiment where the PLC can control the HVAC system based on temperature and humidity sensors and user inputs to maintain a desired consistent temperature. The PLC will be controlled using Unity Pro XLS/Control Expert software for simulations. The overall purpose of the experiments will be to demonstrate the potential of the PLC to minimize manual intervention while …

Standalone Wireless Humming Music Synthesizer, Elizaveta Viktorovna Koush, Conrad Kinsey, Alberto Munoz

Electrical Engineering

This project, called a standalone wireless humming music synthesizer, aimed to provide a tool for musicians to make creating music easier. It did this by removing learning barriers and adding an assistive functionality element that current synthesizers fail to address.

Existing methods for synthesizers typically include a keyboard or some collection of buttons to play melodies on. This requires the knowledge of music theory and a learning curve for the instrument, and this device aims to tackle this barrier. A device that can synthesize your voice into high-quality audio removes this musical knowledge barrier and allows anyone to easily convert …

Mars Prototype Rover Environmental Measurement System, James A. Renick

Computer Engineering

In my senior project, the problem I am trying to solve is how to efficiently design, create, and install an original library onto a Mars prototype rover operating system and to further use that library to integrate a new weather measurement sensor device into the rover system with the necessary software and hardware implementations. This is an important and highly valued problem as many aerospace and other engineering companies utilize rovers and other autonomous systems for important research, explorations, and reconnaissance missions and goals. In solving this problem, I utilized many resources that were available to me such as advisors, …

Multifamily Complex Smart Locks For Property Management And Tenant Security, April Mills, Allen Chen, Dana Kumamoto, Michael Cook

Mechanical Engineering

Maintaining and managing hundreds of locks and physical keys for an apartment complex can be time consuming and costly, especially when the apartments turn over to new tenants. Our goal was to develop a smart door lock that is compatible with Obodo’s management app for apartment complexes to make accessing apartments secure and simpler for tenants and easier to manage for owners.

We designed and manufactured one smart door lock that is powered with four AA batteries and utilizes a dynamic NFC device and Bluetooth technology. The board can enter a sleep mode which reduces power consumption. The dynamic NFC …

X-Band Rf Transmitter Design For Multi-Purpose Small Satellite Communication Operations, Omer F. Gumus

Master's Theses

This thesis provides a description of the analysis, design, and tests of an X-band RF Transmitter communication system for small satellites. X-band transmitter systems are becoming popular in the upcoming deep space missions. Most of the deep-space ground stations have been using X-band frequencies to receive or transmit signals. The X-band (<10 GHz) can offer lower atmospheric losses and up to a couple of Mbps data rates for multiple satellite operations. Nowadays, many small satellites have been using frequency bands such as VHF, UHF, L, and S-band frequencies for communication. From deep space to the ground station, the low-frequency ranges are inadequate in providing Mbps level data rates and enough bandwidth for deep space missions.

The main focus of this thesis was the development of the subsystems such as gain block amplifier, Mixer, Bandpass Filter, and RF power amplifier. The subsystems were designed separately, then they were connected together to perform an end-to-end system test. One of the thesis aims is to design …

Design Of An Automotive Iot Device To Improve Driver Fault Detection Through Road Class Estimation, Matt Murray

Master's Theses

Unsafe driver habits pose a serious threat to all vehicles on the road. This thesis outlines the development of an automotive IoT device capable of monitoring and reporting adverse driver habits to mitigate the occurrence of unsafe practices. The driver habits targeted are harsh braking, harsh acceleration, harsh cornering, speeding and over revving the vehicle. With the intention of evaluating and expanding upon the industry method of fault detection, a working prototype is designed to handle initialization, data collection, vehicle state tracking, fault detection and communication. A method of decoding the broadcasted messages on the vehicle bus is presented and …

Smartphone Control Of Rc Cars, Weston R. Fitzgerald

Electrical Engineering

The smartphone-controlled RC (remote-controlled) car is an inexpensive remote-controlled car designed to be fast and portable. Instead of manufacturing, packaging, and shipping a separate controller, the remote control is implemented in a phone application, which saves time and money in both the design process and the manufacturing process. Utilizing the user’s smartphone is more cost-effective since mobile devices are a common recurrence, and packaging fewer devices results in overall better portability of the product.

This smartphone-controlled car is speedy and intuitive to learn for typical smartphone users. The user can change the car’s speed and direction wirelessly using their phone; …

Behind The Ear (Bte) Hearing Aid, Marco Gaitan, Jaclyn Kimoto, Lawrence Lai, Billy Pho

Electrical Engineering

The product is a Behind The Ear (BTE) hearing aid with the capability to improve the quality of life for people with mild to severe hearing loss and caters to a different consumer through bold exterior design to increase awareness of deafness and normalize hearing loss. In comparison to In The Ear (ITE) and In The Canal (ITC) hearing aids, the BTE hearing aid provides the best amplification while retaining an affordable price. Sound amplification depends on two or more directional microphones embedded in the product to give users the ability to discern the direction of incoming sound easily in …

Microgrid Energy Storage Branch, Evan Luu, Jeffrey Shieh

Electrical Engineering

The microgrid is the future for the electrical utility system. Because of this, future power engineers need to be well-versed in this topic when they go into industry. Cal Poly has created a microgrid laboratory for this very purpose. However, it is missing its battery based energy storage branch. Due to safety concerns, a traditional chemical battery is not suitable for student use. In order to maintain Cal Poly’s learn-by-doing approach, an alternative solution must be implemented. A regenerative power supply meets the criteria for student use. It is capable of simulating the sinking and sourcing capabilities of a battery …

Multi-Effect Guitar Pedal, Ryan K. Madden

Electrical Engineering

This product is a multi-effect pedal to be used with an electric guitar. This unit can distort and overdrive the weak signal from a guitar as well as add chorus, phaser, and compressor effects to the signal. Additionally, the user can choose different serial combinations of the effects, allowing full creativity and experimentation with a multitude of signal chain options. This product, having many different effects, saves space than if the effects were all individual devices. To interact with the product, there is a user interface with buttons, LEDs, and an OLED screen to allow the user to customize the …

Carrier Card For Nvidia Jetson Agx Xavier, Kyle Chang

Electrical Engineering

This project prototypes and implements custom carrier cards for interfacing with the Nvidia Jetson AGX Javier within the Zendar Processing Unit (ZPU). The Jetson module is an AI computer used as a computing system for autonomous machines, including robots, drones, and self-driving cars. The carrier card functions as an I/O interface with the Jetson module, and it is designed for and sponsored by Zendar, a start-up designing high-resolution radar imaging systems. The purpose of the carrier card is to function as a collection of multiple I/O interfaces, including HDMI, USB, and PCIE, for users to control the Jetson, to input …

Installation Of Electrical System For Paso Robles Police Department, Peter D. Strykers, Jacob M. Studebaker

Construction Management

This paper outlines the process that Peter Strykers and Jacob Studebaker went through to set up the lighting and power system for the Paso Robles Police Department gun range located off highway 46. Before our installation, the gun range had zero lighting so the officers could not use it after sunset. We allowed the officers to light the gun range with outdoor LED lights, light up both the storage units on site, and have access to multiple outlets inside and out of the storage units. The power source that the electrical system runs on comes from a Kubota generator because …

Insole Fall Prevention Device, Nick M. Hughes, Andrew M. Slaboda

Biomedical Engineering

Falls among the aging population occur every single day, with 1 in every 5 resulting in some injury and 300,000 hospitalized every year with a hip fracture [1]. The most popular and effective way to mitigate these falls is through physical therapist intervention. However, with the increased popularity in telerehab, many patients at risk for falls cannot accurately convey their gait tendencies to their physical therapists from the comfort of their home or while not in direct contact with the PT. A device like an insole, implanted with force sensors, which measures different parts of a patient’s foot, could convey …

Load Slammer Design For Dc-Dc Converter Testing, Jonathan Hidalgo, Quinton Lacomb

Electrical Engineering

In this work, we dive into the detailed design of a test load or load slammer circuit for DC/DC converters to ensure their correct functioning. This is accomplished through quick variations in frequency, amplitude, and duty cycle of the current being drawn by the converter into the load. Computer simulations of the design were performed using LTSpice and the results show that the load current could be varied per design objectives. Hardware implementation of the design was also conducted and then tested. Results were then compared with the design requirements at lower currents to evaluate the validity of the design. …

Integration Of Electrical Impedance Spectroscopy For Multichannel Cell Culture Measurement, Conard Chan

Master's Theses

ELECTROCHEMICAL IMPEDANCE SPECTROSCOPY (EIS) has been widely used to study the electrical properties of biological material due to its non-invasive nature and experimental reliability. However, most of the precision impedance analyzers used in EIS only provide single- or two-channel measurements which are inadequate for larger-scale multiplexed measurements, such as those found in modern microfluidic cell culture experiments. The Biomedical Microsystems Laboratory has developed a 16-channel cell culture platform with integrated electrode arrays for monitoring cell growth and electrical properties (i.e., the so-called “electrical phenotype”). In this paper, a system consisting of a 16-channel solid-state analog multiplexer (MUX)paired with a low-cost, …

Reverse Engineering And Enhancement Of Automobile Infotainment System, Cole Brinsfield

Electrical Engineering

In 2011, luxury cars were released with displays built into the center. With modern computing power and technology such as Android Auto or Apple CarPlay, these older infotainment systems degrade the value of cars that are otherwise comparable to 2021 models. This project upgrades the infotainment system of one such car, a 2011 Infiniti G37. Through use of an additional microcomputer in the car, an infotainment upgrade can be achieved. This upgraded infotainment adds navigation, wireless audio, and data display capabilities to the car, while maintaining the functionality of the stock infotainment. While customized for the 2011 Infiniti G37, the …

Indoor Positioning Using Synchronized Ultrasonic Ofdma Signals, Julian Bartolone

Master's Theses

This paper proposes a method of short-range indoor localization using differential phase measurements of synchronized two-tone ultrasonic signals in an Orthogonal Frequency Multiple Access (OFDMA) scheme. This indoor positioning system (IPS) operates at an ultrasonic frequency of approximately 40kHz and synchronizes using an infrared signal. The OFDMA scheme allows for a receiver to process the signals from multiple transmitters continuously without the signals interfering with each other. The phases of the signals are measured using Goertzel Filters, allowing for low-complexity frequency content analysis. A MATLAB simulation using the proposed localization method is performed using four transmitter nodes in the corners …

Printed Circuit Board Design And Layout For Hobbyists, Engineers, And Students, Michael A. Derrenbacher

Master's Theses

Printed Circuit Boards (PCBs) are a ubiquitous element of virtually every electronic system manufactured world-wide. It is not a stretch of the imagination to say that if it’s electronic, there is a PCB in it. PCBs are necessary tools for electronics work, and tools need to have instructions. For better or worse, PCB knowledge is a deep and wide ocean. There is much to cover for even a surface level understanding, and there are deep areas rich in technical expertise. Navigating the ocean of knowledge is treacherous; common knowledge of yore can be downright dubious now. PCB manufacturing and electronics …

Ac/Dc Led Light Bulb Adaptor With Internal Rechargeable Batteries, Esteban A. Rubio, Matthew R. Delaby

Electrical Engineering

To make a sustainable product and provide a temporary source of lights on during emergencies, this project aims to create a small unit that can be attached to a light bulb of any variety and connect it to a socket. Within the device is a rechargeable battery that, when the device is not connected to an 120V AC, 240V AC, or 48V DC power source, will power the light for a short period of time. The battery can be charged during the standard operation of the device and can be powered by the US and EU standard outlet voltages as …

Checkerbot, Sean P. Whitty

Electrical Engineering

This product is able to play a game of checkers against the customer at three different preset difficulties. It can process the board on its turn, and displays its next turn to its opponent by updating the board state via the LEDs. It consists of a laptop screen display, and a computer chip with the programmed ability to process the checkers board and decide its next move. It provides the customer with an opponent that can be modified in difficulty so it can provide however much of a challenge as the customer desires, as well as allowing for a 2 …

High Voltage Dc-Dc Converter Design For Submarine Application, Oscar Ambriz

Master's Theses

In this work a proof of concept for a step-down DC-DC converter used in a high voltage submarine application is presented. The purpose of the converter is to step down a 5000V-6000V input to a 24V output which can serve as an input to a submarine sensor. The completed system consists of two stages where the first stage is an unregulated switched capacitor converter to step down the initial input to a voltage range more appropriate for the selected second stage. The second stage is a regulated flyback converter topology which regulates the final output to the desired 24V. Performance …