Digital Commons Network^™

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 …

Total Sky Imager Project, Ryan D. Maier, Benjamin Jack Forest, Kyle X. Mcgrath

Mechanical Engineering

Solar farms like the Gold Tree Solar Farm at Cal Poly San Luis Obispo have difficulty delivering a consistent level of power output. Cloudy days can trigger a significant drop in the utility of a farm’s solar panels, and an unexpected loss of power from the farm could potentially unbalance the electrical grid. Being able to predict these power output drops in advance could provide valuable time to prepare a grid and keep it stable. Furthermore, with modern data analysis methods such as machine learning, these predictions are becoming more and more accurate – given a sufficient data set. The …

Solar Solution For Mini-Rover, Michaella Ochotorena, Derick Louie, Jonathan Cederquist, Collin Petersen, Cole Korchek

Mechanical Engineering

This project focuses on designing, building, and testing a functional prototype of a collapsible solar array on the mini Mars rover being developed by client and sponsor, Mr. Rich Murray. Although many previous collapsible solar arrays have been deployed for space missions, the previous solar-powered Mars rovers only deployed their arrays once upon landing. This solar array will be able to collapse and deploy multiple times to allow for greater rover mobility and stability when the rover is not charging. This system is critical to the success of the rover project because it provides power without which the rover cannot …

Bike To The Future, Wanjiku Gichigi, Luisa Shu Yi Chiu, Alexander Kalman Dunn, Georgia Ann Holmes

Mechanical Engineering

Brian Higgins is a veteran with retinitis pigmentosa who enjoys biking. The motivation for this project was to design and manufacture a refined prototype of a bike attachment to assist Brian in safely biking to and from work. The customer needs, problem definition, background, design development, final design, testing, costs, and recommendations are provided in this report.

The solution for this project, as laid out in the design development section, was to design an assembly that would detect objects in the biker’s path and relays that information to them. The design incorporated a dashboard to conceal components within, protect them …

Baker/Koob Final Report: Solar Solution For Mini Mars Rover, Jonathan Cederquist, Cole Korchek, Derick Louie, Michaella Ochotorena, Collin Petersen

Mechanical Engineering

This project focused on designing, building, and testing a functional prototype of a collapsible solar array on the mini Mars rover being developed by client and sponsor, Mr. Rich Murray. Although many previous collapsible solar arrays have been deployed for space missions, the previous solar-powered Mars rovers only deployed their arrays once upon landing. This solar array will be able to collapse and deploy multiple times to allow for greater rover mobility and stability when the rover is not charging. This system is critical to the success of the rover project because it provides power without which the rover cannot …

Skip The Grid: Giving Power To Navajo Nation, Ryan J. Schacherbauer

Construction Management

Skip the Grid is a project organized by Heart of America, a nonprofit, looking to improve the education and overall wellbeing of children and their families. Many residents within Navajo Nation do not have access to continuous power and rely on temporary generators or car battery to obtain any kind of electricity. Heart of America partnered with the Red Mesa School District to identify families that did not have power, which was impacting the children’s ability to complete their online schoolwork. This senior project was comprised of an interdisciplinary team responsible for installing a working solar system on twelve homes …

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 …

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 …

Controlling Temperature Of Dc-Dc Converter Using Switching Frequency Adjustment, Sajjad Ahsan, Arsalan Mughal, Mark Rapiz

Electrical Engineering

As DC-DC converter operates under different load conditions, the amount of loss within the converter varies accordingly. Consequently the temperature of the DC-DC converter will also change based on the load demand. For PWM based DC-DC converters, one factor that contributes to the loss; thus, the increase in temperature is the switching frequency at which the converter operates. The higher the switching frequency used, the bigger the switching loss and in turn the hotter the converter. In this project, the temperature of a DC-DC converter is controlled by changing the switching frequency used by the converter. The hardware investigation used …

Hybrid Ac/Dc House: The Road To A Sustainable Future, Nicholas Mcadams, Luis Rodriguez

Electrical Engineering

The Hybrid AC/DC house is a sustainable alternative to preexisting residential power systems. The implementation of a DC bus in current homes will allow inefficient DC-AC and AC-DC conversions to be circumvented. This provides a direct path for current to flow to DC loads from DC sources such as solar panels to minimize power losses. In doing so, this will give users the ability to power their homes strictly from renewable sources and substantially decrease reliance on the utility. For this purpose, the hybrid AC/DC house is also designed in such a way to be entirely grid-independent to provide power …

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 …

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 …

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 …

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 …

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 …

Microgrid Laboratory Wind Energy Integration, Vincent Liang

Master's Theses

Cal Poly San Luis Obispo’s Electrical Engineering Department and the Power Energy Institute have developed a microgrid laboratory with various generators, loads, and protection systems over the past several years. To improve and make the Cal Poly microgrid laboratory more realistic, this thesis outlines the process of improving the EE microgrid setup by adding a wind energy generation system via an induction generator, excitation capacitors, and a protection relay. By adding an induction generator, the microgrid system becomes more resilient to sudden power fluctuations by maintaining a stable voltage and frequency when the microgrid is islanded. To test this, 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 …

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 …

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 …

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 …

Integrating Fire Responses To Combat Wildfires, Jonathan Leonard Badal

Electrical Engineering

Each year wildfires cause significant loss of property, worsen people’s health, and destroy multiple ecosystems. On average, a wildfire season costs anywhere from 7.6-62.8 billion dollars due to fire containment, repair, and restoration [1]. It can take decades to recover from the crippling loss of land and take even longer to fully restore it. However, with the implementation of a robust early detection system, these losses can be significantly reduced. The current process for identifying wildfires involves visual identification, phone call alerts, and media tools primarily driven by park rangers and public reporting. Unfortunately, this system is not preventative and …

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. …

Smart Motor Syringe System, Connor Wilson

Electrical Engineering

In this document a proof-of-concept design is developed and implementation to showcase the latest development in an ongoing effort to produce a series of automated syringe pumps.

Verification Of A Digital Microfluidics Platform, Karanpartap Singh

Electrical Engineering

The electrowetting effect describes the change in contact angle between a solid surface and electrolyte in response to an applied electric potential difference. Given a planar array of individually-actuated electrodes, electrowetting can be used to transport, mix, and separate picoliter to microliter-sized droplets of liquid on a dielectric layer. Applications of this phenomenon range from lab-on-a-chip and other microfluidic devices to liquid lenses capable of altering their topology and focus within milliseconds.

This project extends prior work simulating the dependence of droplet velocity on actuation voltage and demonstrates observed physics on a physical platform. The simulation portion of this project …

Impact Of Teaching Practices And Communication Climates On Participation In Computer Science Education, Jackie Krone

Master's Theses

One way to understand teaching is to view it as a people process rather than a presentation of knowledge. It follows that the role of an educator often extends beyond the primary subject matter and into the realm of classroom management. With this in mind, our research aimed to capture the various teaching practices, participation patterns, and communication climates that occur in virtual computer science classrooms. We sought to answer the following research questions related to virtual computer science classrooms at our institution: Who participates in virtual computer science classrooms, and is participation proportional to student demographics? Is there any …

Investigation Of Green Strawberry Detection Using R-Cnn With Various Architectures, Daniel W. Rivers

Master's Theses

Traditional image processing solutions have been applied in the past to detect and count strawberries. These methods typically involve feature extraction followed by object detection using one or more features. Some object detection problems can be ambiguous as to what features are relevant and the solutions to many problems are only fully realized when the modern approach has been applied and tested, such as deep learning.

In this work, we investigate the use of R-CNN for green strawberry detection. The object detection involves finding regions of interest (ROIs) in field images using the selective segmentation algorithm and inputting these regions …

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 …