Engineering Commons^™

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 …

Spacecraft Trajectory Optimization Suite: Fly-Bys With Impulsive Thrust Engines (Stops-Flite), Aaron H. Li

Master's Theses

Spacecraft trajectory optimization is a near-infinite problem space with a wide variety of models and optimizers. As trajectory complexity increases, so too must the capabilities of modern optimizers. Common objective cost functions for these optimizers include the propellant utilized by the spacecraft and the time the spacecraft spends in flight. One effective method of minimizing these costs is the utilization of one or multiple gravity assists. Due to the phenomenon known as the Oberth effect, fuel burned at a high velocity results in a larger change in orbital energy than fuel burned at a low velocity. Since a spacecraft is …

System Identification Of A Cantilever Beam With Interferometer Measurement Using Adaptive Filters, Jordan D. Kochavi

Master's Theses

Laser interferometry, commonly used in high-precision motion control systems, is rarely adopted in experimental vibration analysis because its installation and mounting is invasive to dynamical systems. However, metrology systems that already utilize laser interferometry, such as profilometry in semiconductor manufacturing, may benefit from interferometer feedback for signal processing. This study investigates the use of laser interferometry for system identification through a piezoelectrically actuated cantilevered beam.

The model of the beam including piezo actuators and optical measurement components are established through the Euler-Bernoulli beam theory. From the method of separation of variables, the continuous system is transformed into a discrete system …

The Effects Of Atomic Oxygen On Silicone And Carbon-Based Contamination, Mayana W. Gordon

Master's Theses

Understanding the space environment and contamination concerns of a spacecraft is critical in designing a successful mission. The ability for a spacecraft to meet its science objectives relies on systems functioning as intended. A concern for maintain- ing performance while on orbit is molecular contamination. Silicones have previously been shown to form a silica layer on their surfaces when exposed to atomic oxygen. For silicone contamination, this translates to a silica film on the contaminated surface. Missions such as Long Duration Exposure Facility and Evaluation of Oxygen Interactions with Materials III have indicated that the silica film can trap deposits …

Design Justice In Community-Oriented Engineering Pedagogy And Practice, Michael S. Reyna

Master's Theses

While engineering service-learning projects are seen as a favorable way for students to reinforce curricular learning while gaining cultural awareness, the outcomes of these projects center student benefits over partner community wellbeing. For these projects, and in other engineering contexts, various scholar-activists have conceptualized numerous principles and methods to center justice and equity in engineering outcomes. This research project and its associated intervention involved collecting scholarship and methods in engineering and social justice, and attempted to integrate these ideas into the practices of a local humanitarian service-learning engineering team. The collected scholarship centered around the topics of Design Justice, feminist …

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 …

Design And Analysis Of N-Path Filter For Radio Frequencies, Nathan M. Bergen

Master's Theses

Due to the growth of wireless communication many communication frequencies have grown increasingly dense. This density requires higher Q-factor to receive only the signal of interest. With the rise of smaller integrated circuits previous solutions used for filtering have become viable again. This paper explores whether the N-path filter is viable in the modern day for radio frequency receiver purposes. A non-differential N-path filter was created by utilizing Cadence Virtuoso with a working center frequency range of 750MHz to 1GHz while using TSMC technology. The desired quality factor of over 1,000 was reached while maintaining a total area of 800 …

Measuring Accessibility For Pedestrians, Bicyclists, And Transit Riders To Grocery Stores In The Excelsior/Outer Mission Neighborhoods Of San Francisco, Alexandra Lee-Gardner

Master's Theses

Grocery stores are an important amenity in neighborhoods and access to grocery stores is important for health and well-being. While grocery store accessibility is a popular topic of research, studies measuring access for pedestrians, bicyclists, and transit riders are extremely rare. When a new store opened in the Excelsior/Outer Mission districts of San Francisco on a street lacking basic infrastructure for pedestrians, bicyclists, and transit riders, the importance of this study became apparent. The Excelsior/Outer Mission neighborhood has a shocking number of collisions (over 1,100 between 2015 and 2019), elevated levels of walking, biking, and transit ridership, and minimal safe …

Modeling And Control Of A Planar Bounding Quadrupedal Robot, Patrick John Ward

Master's Theses

Legged robots have the potential to be a valuable technology that provides agile and adaptive locomotion over complex terrain. To realize legged locomotion's full abilities a control design must consider the nonlinear piecewise dynamics of the systems. This paper aims to develop a controller for the planar bounding of a quadrupedal robot.

The bounding of the quadruped robot is characterized by a simplified hybrid model that consists of two subsystems for stance and flight phases and the switching laws between the two states. An additional model, the Multibody model, with fewer simplifications, is used concurrently to best approximate real-world behavior. …

Design Of A Proprioceptive Actuator Utilizing A Cycloidal Gearbox, Craig John Kimball

Master's Theses

Legged robotics creates the demand for high torque compact actuators able to develop high instantaneous torque. Proprioceptive actuator design theory is a design theory that removes the need for a torque feedback device and relies on the stiffness in the leg for absorbing the high Ground Impact Forces created by walking locomotion. It utilizes a high torque density motor paired with a gearbox with a high gear ratio for torque multiplication. Previously work has been done to design a proprioceptive actuator design that utilizes a planetary gearbox to create a modular low-cost actuator for legged robotics. The purpose of this …

Feasibility Report On Water Recycling And The Housing Crisis, Tally A. Perry

City and Regional Planning

The western United States is experiencing increasing population, a housing shortage, and a drought. These challenges demand creative and unprecedented changes to development. Water recycling is slowly emerging as a viable solution for developers, home owners, and cities as a way to continue much-needed housing development while mitigating unnecessary water depletion. With all change, policy, feasibility, and awareness can be the largest influencers. Drought-ridden western-American states require additional and revised regulatory requirements to promote recycled water in new development. Currently, water reuse is largely used for agricultural and industrial purposes. To motivate and encourage housing development, water recycling needs to …

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 …

Current-Source Dc-Dc Converter, Rocio Sanchez-Mendoza, Carlos Aguilar, Adrian Aranjo

Electrical Engineering

In this project, a hardware implementation of a current-source DC-DC converter for powering sensors used in an underwater communications system is presented. The proposed converter is designed to step 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. An overview of the system design is explained as well as the component selection process. The design of the converter was simulated and evaluated using LTspice before being physically constructed on a printed circuit board. Performance evaluation of the proposed converter was carried out in multiple lab …

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 Rover Structure, Ethan Nikcevich, Justin Marhoefer, Will Kish, Brenden Billing

Mechanical Engineering

Our project is the third iteration of a design to create a small Mars rover. Our main challenge was to change the existing rover structure into something that could survive the harsh conditions of Mars. This meant altering the design so that it could resist the large temperature fluctuations while still maintaining the structural stability and interface to support driving functions and the projects of the other rover teams. Our team accomplished this goal by altering the design of the existing rocker bogey from completely 3D printed to a tube and joint system. The longer portions of the rocker bogey …

Self-Balancing Bicycle Device, Charles Cole, Raffy Lorenzo, Neil Boyal

Biomedical Engineering

The sponsor, Justin Shaw, is currently developing a bicycle for an athlete who has lost movement in their legs. This athlete can no longer experience the unmatched feeling of naturally banking a bicycle at corners. The Self-Balancing Bike Device Team will create a device that can self-balance an electric recumbent bicycle at low speeds while being almost undetectable while turning. This document will outline the team’s background research into self-balancing vehicles, define the needs that must be solved, and delineate a schedule for future milestones.

Rod Bend Approximator For Minimally Invasive Spinal Surgery, Amanda Hansell, Anise Ghandchi, Shervin Moghimi

Biomedical Engineering

This Final Report will go over the project deliverables and future steps in the making of a rod bending approximator tool by the Cal Poly Senior Design team for the client SeaSpine. The latest designs and research done regarding minimally invasive surgery (MIS) is covered including the impediments with the current methods. SeaSpine presented the need to our team for an approximating tool within the MIS procedure. Our team began project planning through task generation and schedule development. Once the product definition was fully understood, competition was evaluated and engineering specifications were created for the project. A conceptual design was …

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, …

Researching The Impact Of Cal Poly Classes On Computing Students Perceptions Of Computer Ethics And Social Responsibility, Annie Joss

Computer Engineering

The importance and impact of socio-technical systems are playing an increasing role in the education of computing students. Discussion of ethics and social responsibility has always been a tenant of computer science education; however, research has shown engineering and computer science students lose focus on these values over their engineering education. Cal Poly computing departments have taken steps to emphasize social responsibility and ethics through required and suggested courses. This project focuses on examining the values and beliefs of Cal Poly computing students, who were surveyed over Winter and Spring Quarters in 2022. This project is inspired by Dr. Cech’s …

Developing A Miniature Smart Boat For Marine Research, Michael Isaac Eirinberg

Computer Engineering

This project examines the development of a smart boat which could serve as a possible marine research apparatus. The smart boat consists of a miniature vessel containing a low-cost microcontroller to live stream a camera feed, GPS telemetry, and compass data through its own WiFi access point. The smart boat also has the potential for autonomous navigation. My project captivated the interest of several members of California Polytechnic State University, San Luis Obispo’s (Cal Poly SLO) Marine Science Department faculty, who proposed a variety of fascinating and valuable smart boat applications.

Smart Bottle Ble Integration, Joshua M. Rizzolo

Electrical Engineering

In 1975, four percent of children aged five to nineteen were categorized as overweight or obese. As of 2016, this figure climbed above 18 percent [1]. Researchers at California Polytechnic State University San Luis Obispo (Cal Poly) want to investigate the effect of overeating in early childhood on later childhood obesity. This research requires collecting feeding pattern data on infants, which proves challenging. Parents cannot be relied on to regularly collect clean data due to factors including work schedule, multitasking, and general exhaustion. Thus, we have developed a tool to automatically collect data on feeding frequency and duration, as well …

Maximum Trapping Focal Length In Photophoretic Trap For 3d Imaging Systems, Jason M. Childers

Electrical Engineering

This product is a photophoretic trapping system which allows varying focal lengths to test which focal lengths are possible for trapping toner particles. This system establishes that there exists a maximum trapping distance limitation and is the first time the effect of focal length is studied in a photophoretic trapping system. Increasing photophoretic trapping focal length is necessary for improving this technology as a 3D display. The 3D imaging technology is realized by dragging a microscopic (micrometer-scale) particles with a laser beam to trace an image. This technology can display fully colored and high-resolution 3D images visible from almost any …

Signal Adc Converter Simulation On Cadence Virtuoso For Audio Applications, Maxwell Kazuki Fukada

Electrical Engineering

Audio signals are representations of sounds with a mixture of multiple analog signals between the frequency of 20Hz to 20,000Hz. To record snippets of audio data onto a mobile phone or computer, the signal needs to be converted to a digital format. For this purpose, many devices utilize a converter, specifically a sigma-delta modulator with a digital filter. By using a converter, electronics can receive binary data about the audio signal accurately and quickly without losing important signal information. This project aims to simulate a fully functional audio converter with a sigma-delta modulator and decimation filter. The system will receive …

Bicep Muscle Rep Counter With Semg, Matthew Max Garcia

Electrical Engineering

The Bicep Muscle Rep Counter with SEMG is a device that was made to develop three repetition thresholds or difficulty levels from a fully-flexed bicep brachii muscle and signal to the user when consequent bicep muscle contractions pass said thresholds or levels. This device can be used when performing a bicep-focused movement or when generally flexing the bicep muscle. Essentially, this device serves to make sure each repetition of a muscle contraction passes a percentage value calculated from the electrical activity outputted from a max contraction.

The device is not designed for and does not produce data for muscle growth, …

Hum Synthesizer, Daniel Keith Mcfall, Jason Chang

Electrical Engineering

Most modern music, especially the popular and rising genres such as pop music and rap music are more reliant on music synthesizers than ever before. While other instruments are readily used to sample background noises, the main form of sound generation is becoming more digital rather than using acoustic instruments. However, many people that want to make music aren’t familiarized with traditional music theory and would have difficulty using a traditional synthesizer. The Hum Synthesizer aims to allow a wider audience to access the functions of a traditional synthesizer by using voice controls rather than keyboard controls. If the user …

Teaching Intro To Web Development With React, Rey Ortiz

Computer Science and Software Engineering

Throughout the years, the field of computer science has increasingly become in demand and it is projected that in the next decade, job prospects are expected to grow much faster than the average rate for all occupations. With the reliance of technology in our daily lives and technology always evolving, the need for professionals with backgrounds in computer Science has risen dramatically. One of the things that we as educators can do to bridge this gap is to introduce students to web development at the beginning of their college career to get more students interested in the field of computer …

Interactive Lego Girl Scout Arm, Christopher Suzuki, Emi Okuyama, Bryson Shores, Karina Sandoval

Mechanical Engineering

This Senior Project Report document outlines the senior design project for Girl Scouts of California’s Central Coast (GSCCC) led by a team of four Mechanical Engineering students at California Polytechnic State University, San Luis Obispo. The project encompasses the researching, designing, prototyping, and testing of a LEGO robotic arm for the Girl Scouts to learn more about STEM (Science, Technology, Engineering, and Mathematics) and provide support to each Girl Scouts cookie sales in their stores. Their goal was to build a LEGO robotic arm that will interact with customers at the Girl Scout stores and promote the girl scouts' interest …

Mmteg Heatsink Design, Peyton Nienaber, Kadin Feldis, Alec Savoye, Jack Waeschle

Mechanical Engineering

In this document, Cal Poly Senior Design Team F16 presents a summary of its work developing a suitable heatsink for Gas Technology Institute’s Methane Mitigation Thermoelectric Generator. After several months of iterating between experimental testing and simulated heat transfer, a suitable prototype was selected for use in further refining simulation parameters. This was called the structural prototype and it allowed Team F16 to confirm several remaining unknowns relating to component thermal conductivity. All documentation of this process can be found in Preliminary, Critical, and Interim Design Review documents (PDR, CDR, IDR), included in this report. Having a realistic model …

Mtb Daq - Mountain Bike Data Acquisition System, Theodore J. Philliber, Ronan M. Shaffer, Dylan M. Ruiz, John M. Ringrose

Mechanical Engineering

Mountain bike suspensions systems are set up and tuned based only on qualitative, ‘feeling’-based metrics. The MTB DAQ, sponsored by Dr. Joseph Mello with the Cal Poly Mechanical Engineering Department, is a data acquisition system we developed to improve suspension tuning with a data-driven approach. The system mounts to a bicycle frame and has sensors that measure vibration and travel speed to characterize the bike’s motion. While similar systems exist, they cost in the thousands of dollars range and are very specific to individual bike geometry. Our system was designed to be more affordable to the average rider as well …