Engineering Commons^™

An Exploratory Study Of Pulse Width And Delta Sigma Modulators, Logan B. Penrod

Master's Theses

This paper explores the noise shaping and noise producing qualities of Delta-Sigma Modulators (DSM) and Pulse-Width Modulators (PWM). DSM has long been dominant in the Delta Sigma Analog-to-Digital Converter (DSADC) as a noise-shaped quantizer and time discretizer, while PWM, with a similar self oscillating structure, has seen use in Class D Power Amplifiers, performing a similar function. It has been shown that the PWM in Class D Amplifiers outperforms the DSM [1], but could this advantage be used in DSADC use-cases? LTSpice simulation and printed circuit board implementation and test are used to present data on four variations of these …

Video Based Automatic Speech Recognition Using Neural Networks, Alvin Lin

Master's Theses

Neural network approaches have become popular in the field of automatic speech recognition (ASR). Most ASR methods use audio data to classify words. Lip reading ASR techniques utilize only video data, which compensates for noisy environments where audio may be compromised. A comprehensive approach, including the vetting of datasets and development of a preprocessing chain, to video-based ASR is developed. This approach will be based on neural networks, namely 3D convolutional neural networks (3D-CNN) and Long short-term memory (LSTM). These types of neural networks are designed to take in temporal data such as videos. Various combinations of different neural network …

Smart Solar Charge Controller, Aria Pegah, Miclaine Emtman

Electrical Engineering

The technology of photovoltaics has been quickly evolving as we move toward a future with more clean energy. Energy conversion efficiency is key to making these systems the viable option amongst other sources of power. This project proposes a way to increase the power yield from a solar system by implementing smarter algorithms in the maximum power point tracking (MPPT) component of the system. MPPT is critical because environmental conditions may vary significantly for any given system due to irradiance and shading. The proposed method for MPPT utilizes a controller that uses swarm intelligence to do the power tracking.. This …

Dc-Dc Buck-Boost Converter Design For Energy Harvesting From Exercise Equipment, Nicholas Serres

Electrical Engineering

This project aims to improve energy harvesting efficiency from an exercise machine. Exercise machine energy harvesting has a small immediate impact but can eventually have an immense impact. An elliptical exercise machine energy converter outputs 5V-60V whereas the microinverters require approximately 36V. The buck boost DC-DC converter bridges the gap between the microinverter and the elliptical machine. Increasing the buck-boost controller efficiency increases power production. Greater power efficiency gives the whole system more financial viability, and additionally makes it a greater sustainable energy source.

Programmable Battery Management System, Jason Erbert

Electrical Engineering

Lithium batteries provide excellent energy storage capabilities at a relatively high density; however, precautions must be taken with these high energy devices to ensure safe operation. A battery management system (BMS) provides protection by monitoring cell and pack voltage levels and maintaining them in a specific range. They limit the output current and disable the output in extreme conditions. Most devices in the targeted power range (<1000W) do not allow the user to manipulate the values for maximum current, cut-off voltage, or other limits. This project introduces the Programmable BMS (PBMS), which instead allows the user to select these values through a physical interface. The interface displays measurements including pack voltage and output current, and it reports additional characteristics of interest such as the battery’s temperature, state of charge, and cumulative number of charge cycles. This level of access and control permits users to receive the maximum performance and safety from common lithium battery packs.

Smart Motor Syringe System, Conard Chan, Jenny Chiao

Electrical Engineering

Syringe pumps are widely used in many research applications especially in the applications that need precise control. Today most medical research utilizes syringes to control the fluid being pumped to the experiment objects. In most cases microscopic or nano-scopic motion control is required to acquire optimal results, such application includes purification of DNA/RNA from contaminants[1]. The high precision required to control the syringe pump makes it difficult to perform manually. This paper focuses on the design of an intelligent syringe pump motor control system to achieve reliable and precise control for biomedical experiments. This project improves medical research quality with …

Simulation Of An Sp8t 18 Ghz Rf Switch Using Smt Pin Diodes, Andre De Souza Vigano

Master's Theses

Radio frequency (RF) and microwave switches are widely used in several different applications including radar, measurement systems, telecommunications, and other areas. An RF switch can control a radar’s transmit vs. receive mode, select the operating band, or direct an RF signal to different paths. In this study, a single pole eight throw (SP8T) switch using only Surface Mount (SMT) components is designed and simulated in Keysight’s Advanced Design System (ADS). Single pole eight throw is defined as one input and eight possible outputs. A star network configuration with series-shunt PIN diode switches is used to create the 8-way RF switch. …

Field Testing The Effects Of Low Reynolds Number On The Power Performance Of The Cal Poly Wind Power Research Center Small Wind Turbine, John B. Cunningham

Master's Theses

This thesis report investigates the effects of low Reynolds number on the power performance of a 3.74 m diameter horizontal axis wind turbine. The small wind turbine was field tested at the Cal Poly Wind Power Research Center to acquire its coefficient of performance, C­_p, vs. tip speed ratio, λ, characteristics. A description of both the wind turbine and test setup are provided. Data filtration and processing techniques were developed to ensure a valid method to analyze and characterize wind power measurements taken in a highly variable environment. The test results demonstrated a significant drop in the …

Iot Camera System For Monitoring Strawberry Fields, Simon Schoennauer

Master's Theses

A wireless imaging system for monitoring strawberry fields provides enough quality image data for computer vision algorithms to make meaningful yield predictions. This report contains a design for a wireless sensor network modified with mesh networking techniques to extend coverage range and a solar energy harvesting system to improve sensor node lifetime. A two hop system with six nodes is implemented in a laboratory environment validating the communication systems integrity over an 800’ range. Moving from a primary battery system to solar energy harvesting increases the module lifetime indefinitely.

Iot Asset Tracker, Jonny M. Erickson, Matt A. Murray

Electrical Engineering

This senior project will be the completion of an IoT asset Tracker. In today’s day and age, technology is weaving its way into every aspect of life. Because of this, we demand to know more and more information about everything that is going on in our lives. One of these needed pieces of information is knowing the location of our most valuable assets. This is the main goal of this project: to build a portable SMS driven GNSS tracking device. The device is designed to provide two methods of tracking for any mobile asset. The device will utilize a large …

Exploration And Comparison Of Image-Based Techniques For Strawberry Detection, Yongxin Liu

Master's Theses

Strawberry is an important cash crop in California, and its supply accounts for 80% of the US market [2]. However, in current practice, strawberries are picked manually, which is very labor-intensive and time-consuming. In addition, the farmers need to hire an appropriate number of laborers to harvest the berries based on the estimated volume. When overestimating the yield, it will cause a waste of human resources, while underestimating the yield will cause the loss of the strawberry harvest [3]. Therefore, accurately estimating harvest volume in the field is important to farmers. This paper focuses on an image-based solution to detect …

Boost Converter Inductor Sizing Effects On The Performance Of Mppt Algorithms, Alan Nonaka

Master's Theses

With solar power and other renewables set to take over the market in the coming decades, maximum power point tracking will be essential to optimizing power output. One underserved topic of research is the effect of inductor current ripple on performance of Maximum Power Point Tracking (MPPT) algorithms. Many new topologies are focused on decreasing the ripple from PV source to increase efficiency and power output. However, not much has been done to show ripple degrading performance of MPPT algorithms. This study uses a boost converter topology to test the performance of constant duty cycle step Perturb and Observe (PO), …

Reading Robot, Gillian Watts, Andrew Myers, Sabrinna Tan, Taylor Klein, Omeed Djassemi

General Engineering

Presently, there is an insufficient availability of human experts to assist students in reading competency and comprehension. Our team’s goal was to create an improved socially assistive robot for use by therapists, teachers, and parents to help children and adults develop reading skills while they do not have access to specialists. HAPI is a socially assistive robot that we created with the goal of helping students practice their reading comprehension skills. HAPI enables a student to improve their reading skills without an educator present, while enabling educators to review the student's performance remotely. Design constraints included: physical size, weight, duration …

Raysun's Infrared Raisin Dryer, Lucas Kensinger, Saraith Aispuro, Joe Vanacore

General Engineering

The RaySuns senior project team was tasked with lowering the drying costs of raisins for River Ranch Raisins. In doing so, we explored several options for cutting costs: utilizing automation and exploring new drying technologies were our primary focus. We eventually planned a modular infrared heating mechanism which would be easy to automate in future projects. After manufacturing and testing an infrared heating mechanism, it was found that infrared drying could significantly cut costs versus the previous natural gas fired dryer tunnels while leaving room for automation. The infrared dryer was also shown to have the potential to create high-quality …

Bi-Directional Dc-Dc Converter, John W. Hamlin, Oscar Ambriz, Luis Onofre

Electrical Engineering

This project was developed with the purpose of creating an efficient energy management system for the DC House project, with a centralized 12V battery system fed by a 48V Multiple Input Single Output Source (MISO). The energy management system will consist of a bidirectional DC-DC converter. During the day when the renewable sources produce enough energy to fulfill the load’s energy demand, the converter will make use of the excess energy by taking a 48V DC input and stepping it down to a 12V DC output in order to charge a 12V 100 Ah battery. When renewable sources can no …

Automated Drone Calibration System, Jackie Kelly Jong-Mee Paik, Zach Nathan Richter, Tyler Wilson Van Den Berg, Ryan Alexander Zhan, Matthew Ward Carlson

Mechanical Engineering

The final design review of the Inspired Flight Calibration Team senior project will detail the process used to complete a verification prototype of a drone calibration device and discuss lessons learned and suggestions for improving this device. Going from brainstorming and conceptual prototyping all the way through verification prototyping and testing, we were able to design a gyroscopic device that met Inspired Flight’s needs for the flight sensor calibration of their drones. The mechanical design involved comprehensive CAD models and hands-on manufacturing. The mechatronics side of the project worked heavily with electrical wiring and writing custom software to communicate and …

Cascaded Voltage Clamping And Ldo Offline Power Supply, Elizabeth Davis, Timothy Jeong

Electrical Engineering

Offline power supplies are necessary for any sort of electronic device that utilizes wall power. For offline power supplies, it is a common practice to use the switching mode method where the high voltage AC input is first rectified and then switched at high frequency to a much lower voltage. This method has been known to be very efficient. Also, it’s more efficient than a linear supply method where the AC input is stepped down and then linearly regulated down to a low voltage. Despite the efficiency benefit, the switching method employs a high frequency transformer and inductor. This will …

Engineering A Grapevine Pruning Training Tool For Use In Educational And Professional Environments, Catherine Anne Thornbury

Electrical Engineering

This report documents the design of a field-safe and portable tool that helps field hands identify how many wine grape nodes to prune per cane. This practice allows for a more bountiful harvest. The device indicates to the worker whether to leave one, two, or three nodes on a cane. The device is attachable to a set of industry-standard shears to allow for efficient and cost-effective pruning.

The device add-on can withstand a typical 8-hour workday and is able to be used in bright sun, clouds, and rain. Additionally, the device is able to differentiate between small, medium, and large …

Dual Axis Solar Panel Tracker, Xavier Joseph Lugue, Javier Harrison, Nicholas Ryan Wolfe

Electrical Engineering

Photovoltaic systems generate more energy when orthogonally facing the sun where solar cells absorb the most light. By creating an effective, autonomous solar tracking system, the developed solar panels consistently generate maximum energy while using less power. Dual axis solar trackers surpass single axis trackers in energy generation, however, their cost and reliability provide a significant drawback. This project develops different algorithmic implementations designed to provide optimal and efficient behavior for photovoltaic systems. These algorithms adjust the solar panel’s position appropriately with the sun’s location, weather conditions, and selected operating modes. The solar tracking system’s operations include latitudinal axis capability …

Polyone Smartphone, Joshua Zalmanowitz, Chi Nguyen, Gerome Cacho, Chris Lim

Electrical Engineering

The Poly One Smartphone is a student designed smartphone built to explore the implementation of 5G, provide a hardware solution to ensure personal information security and privacy, and provide longer battery life. The key features of this smartphone include but are not limited to a main cpu, some form of network connectivity in the form of Wi-fi or Cellular Data, calling functionality, a rechargeable battery that works with common power connection protocols, and compatibility with popular applications.

Conducted And Radiated Emi Measurements Of Parallel Buck Converters Under Varying Spread Spectrum Parameters, Elena Postupalskaya, Nathan Wang

Electrical Engineering

The Conducted and Radiated EMI Measurements with Parallel Buck Converters Under Varying Spread Spectrum Parameters research senior project aims to explore the effects from Spread Spectrum Frequency Modulation (SSFM) on the input electromagnetic interference (EMI) or noise of a switching power supply, specifically with LM53601MAEVM hardware. The input EMI is important as the main input bus needs to be clean to provide a reliable source for other sensitive devices connected to it. SSFM can replace a conventional EMI filter and save weight, space, and cost. This project provides a basis in terms of the impacts of variable SSFM in simulation …

Energy And Economic Losses Due To Soiling On Utility Scale Pv Systems To Guide Timing Of Cost Effective Cleaning, Sophia Mcmillin Stockburger, Vicente Jesus Rios

Electrical Engineering

The purpose of this senior project is to develop and recommend a cleaning schedule for Goldtree Solar Farm that is both economically beneficial and an efficient use of cleaning for the client. Solar farms can have various factors that influence the cleaning schedule such as weather behavior, time of the year, soiling, and other factors. Through this senior project, the goal is to assess these factors effect on the solar farm to produce a cleaning schedule that will maximize energy production, maximize profits, and prevent insignificant cleaning

This analysis is motivated by defining and promoting the benefits of regular maintenance …

Single Axis Solar Panel Tracking Mount Using Stepper Motor And Accelerometer Positional Control, Ezra Pramono

Electrical Engineering

Optimal solar panel systems rotate to track the sun, as solar panels operate at their maximum potential when the panel plane is completely normal to the sun’s rays. These tracking systems often using two axes of movement. This project is to design a system that will allow a solar panel to track the sun using only one rotational axis, which saves energy and uses fewer parts. The system tracks the entire range of the sun's motion and has positional feedback to allow control of the solar panel's angle. The position of the tracking system is controllable via an external computer. …

Photovoltaic Emulator Labview Based Modeling And Simulation, Jeffrey So, Eric Jau Tse

Electrical Engineering

The design goal for this project is to create a system capable of creating a consistent testing environment for photovoltaic inverters and charge controllers. The solution is to create a photovoltaic emulator which is a DC power supply that would have the same electrical output characteristics to a photovoltaic panel. In current systems, consistency problems arise when depending on nature to conduct tests on PV modules because it is impossible to properly replicate scenarios while testing specific conditions. This project will provide the user the ability to test their PV modules under various parameters which replicate real-world scenarios such as …

High Speed, High Current Monitoring System, Nicolette Lila Ray

Electrical Engineering

Electronics testing requires lengthy data collection and analysis. Streamlining at least part of this process allows resource reallocation, and faster data processing. Verifying a signal’s efficiency is key specification for a component’s datasheet. This project focuses on streamlining data collection when measuring a device’s output current. It combines amplifier design and digital interfacing to perform monitor a device’s output current. A computer-enable interface displays a graphical output current representation. It ensures accurate, high speed, high current measurements while removing a person’s need to manually plot data after testing. A new testing method provides room for company and product growth with …

Rf Power Amplifier, Angel De Jesus Delgado, Rachanon Wajanakunakorn, Andrew John Ferguson

Electrical Engineering

Wireless devices are part of everyday life, cellphones and radio receivers impact more people than any piece of technology. Thus, the respective building blocks continue to advance and achieve better performance. A primary component of all wireless communication systems is the power amplifier that drives the antenna. The Institute of Electrical and Electronics Engineers (IEEE) holds the International Microwave Symposium (IMS) every year where teams compete internationally for the most efficient RF Power Amplifier (PA). Power amplifier technologies strive to maximize efficiency and linearity. Topologies to consider are D, E, F, F-1 and Doherty since they have a maximum theoretical …

Fuzz Distortion Guitar Stompbox, James Dennis Cleary

Electrical Engineering

My Fuzz Distortion Pedal offers guitar players a full-fledged fuzz distortion pedal with gain, frequency cutoff and volume controls. The pedal offers a true bypass when inactive which allows the signal to pass through the effect with no coloration. The distortion pedal offers hard clipping of the input signal by amplifying it by a high amount, and then clipping the voltage of the signal through the use of diodes.

Design And Development Of Laboratory Single-Axis Pv Module Tracker, Helen A. Rice, Delaney Berger, Avishek Maitra

Electrical Engineering

Solar energy is an integral part of the renewable energy industry. Advanced solar farms actively track solar movement and update solar panel angles to maximize the system’s output power. Cal Poly boasts its own Solar Farm that features a single-axis tracking system. Single-axis tracking aims to get panels as close to perpendicular as possible given the panel arrangements and given the time of year. Single-axis tracking is a more robust measurement and tracking option. Single-axis tracking systems usually only have East-West panel arc movement, following the sun’s rotation. Dual-axis trackers have both East-West and North-South panel arc movements. Dual-axis systems …

Stability Analysis Of Systems With Time Delay Simulation Program, Matthew Carroll, Brandon Replogle

Electrical Engineering

A small company wants to develop a CAD tool, ideally as part of the MATLAB suite of tools, for system stability analysis of nonlinear control systems with time-delay. The program must allow the designer to input the system block diagram graphically, then using symbolic expansion, automatically generate the Laplace domain stability boundary and disturbance settling time. The stable regions are then to be graphically plotted as a set of 2- or 3-dimensional parametric stability boundaries. The designer can then input performance constraints on the system through the MATLAB console and a Simulink environment will automatically be generated.

This program is …

Wind/Hydro Power Generation Simulator, Justin Shaun Otus, Nicholas Joseph Steele, Patrick Daniel Murphy

Electrical Engineering

This project aims to design a wind or hydro power generation simulator. The original scope of this project was to construct a physical simulation apparatus in which wind/water speed data is fed to a microcontroller that adjusts the control voltage of a motor drive. The spinning DC motor would generate power via a coupled generator whose power output would be a scaled down version of wind/hydroelectric generator power output given the same wind/water speed input. Due to Covid-19, the project was altered to be entirely virtual and was made through Simulink in MATLAB. The virtual simulator attempts to mimic physical …