Engineering Commons^™

Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon

Mechanical Engineering

This report aims to allow our sponsor, to review our design process of the Hitch Cart Landing Gear Prototype. In the design overview section of this report, we discuss the primary design modifications we made to the wheel mechanism of the existing hitch cart prototype, including the addition of the ACME screws and the folding brackets. This allows our sponsor to see the intended improvements made to the past prototype and understand the primary goal of our project. Then, in the implementation section, we cover the entire manufacturing process to allow our sponsor to understand what manufacturing steps must be …

Design Of High Efficiency Doherty Power Amplifier, Kobi G. Kelly, Severin Pindell

Electrical Engineering

The project includes design and fabrication of a high efficiency power amplifier for a student design competition held at International Microwave Symposium (IMS) 2023. Efficient power amplifiers are critical for base station communication requiring efficient use of available power. The final design optimizes power added efficiency (PAE) and linearity. The amplifier will operate at 2.45 GHz. Competitive PAE above 50%, and C/I above 30 dB is achieved by leveraging a Doherty class amplifier using accurate discrete CGH4006P transistor models to simulate an efficient and linear design. Unique design features include optimal transistor bias point selection and power split ratios between …

Engineering An Injectable Hydrogel With Self-Assembling 3d Vasculature, Kendyl Cohn

Master's Theses

This research developed methods for culturing self-assembling capillaries in an injectable gel as a potential method for vascularizing tissue-on-a-chip models to mimic physiological drug delivery. Additionally, a mathematical model was developed as a tool for understanding nutrient delivery and comparison of potential delivery systems. Organs-on-a-chip provide novel platforms for studying biology and physiology in 3D, allow exploration of tissue engineering on a manageable scale, and serve as models for drug screening and drug-delivery testing.

Methods were first developed for co-culture of endothelial cells and fibroblasts (3T3s or HDFs) in 2D, evaluating culture time, seeding density and ratio of HUVECs and …

Manufacturing Silicone In-House For The Creation Of Customized Neurovascular Blood Vessel Mimics, Jacob Wilbert Perisho

Master's Theses

The Tissue Engineering Lab at California Polytechnic State University San Luis Obispo focuses on creating tissue-engineered Blood Vessel Mimics (BVMs) designed for the preclinical testing of neurovascular devices. These BVMs are composed of silicone models, representing anatomically accurate neurovasculatures, that are sodded with vascular cell types and then cultivated in bioreactors (which maintain physiologic conditions). These silicone models are currently sourced externally from industry partners, so the primary goal of this thesis was to develop the means and methods for the Tissue Engineering Lab to manufacture silicone models in-house.

The first aim of this thesis was to develop and explore …

Atascadero Little League - Snack Shack Window Renovation, Anthony J. Catania

Construction Management

Atascadero Little League is an essential part of the local community. It brings families together and provides youth with a place to develop their social skills, sportsmanship, and discipline all while getting outside and exercising. Little leagues are non-profit organizations, managed and operated by volunteers, who sacrifice personal time to give back to their local community. Paloma Creek Park is where Atascadero Little League hosts most of their games. The snack shack’s service window does not face the baseball field, forcing volunteers to rely on a small window in the side of the structure to view their child’s game. The …

Cal Poly's Old Powerhouse Analysis Assessing Stakeholder Preferences, Marissa D. Burns

Construction Management

This research paper delves into the historical and cultural relevance of Cal Poly’s Old Powerhouse, the college’s oldest architectural landmark, which has remained in a state of disuse since the 1990s. Employing meticulous survey methodology; perspectives from faculty, staff, alumni, students, and community members are gathered to illustrate the significance of the Old Powerhouse within the various stakeholders. The study refrains from imposing interpretation but rather seeks to capture the sentiments expressed by stakeholders, providing valuable insights into the building’s perceived value. By centering on the community opinions, the research will underscore the building’s potential and expand on the collected …

Development Of An In Vitro 3-Dimensional Co-Culture Human Colorectal Cancer Model In Microfluidic Devices, Abby Jens

Master's Theses

Colorectal cancer is the second most common cause of cancer-related deaths in the United States, with the relative 5-year survival rate for distant stage cancer being only 14%. The most common treatment for colorectal cancer is with chemotherapeutic drugs; however, the discovery of these drugs is costly, time-consuming, and often requires the use of animal models that do not yield results that translate to clinical trials. Due to these shortcomings, researchers seek to develop physiologically relevant in vitro tumor models that more accurately mimic the tumor microenvironment for cheaper and faster high-throughput drug screening. The aim of this research was …

Comparison Of Scanning Electron Microscopy And Confocal Laser Microscopy For Tissue Surface Roughness Characterization, Tarnvir Dhaliwal

Master's Theses

It was found that the measurements captured by confocal microscopy and scanning electron microscopy had a statistically significant difference for bovine tissue. There was not a statistically significant for porcine and poultry tissue.

The intent of the study is to perform a comparative study to examine efficacy of two distinct technologies for a singular purpose: tissue surface roughness characterization. The two technologies compared are a confocal reflectance microscope and a scanning electron microscope. The comparison was made by comparing two surface roughness parameters [Ra and Rq] within ImageJ.

The study examined three different animal species [porcine, bovine, and poultry] to …

Neonatal Respiratory Therapy Interface, Kennedy Austin, Evan Manley, Parker Murray, Harrison Oen

Biomedical Engineering

This Final Report reviews and outlines the scope, objectives, and deliverables for the BCPAP Interface Redesign project, aimed at enhancing the functionality, usability, and patient experience of the existing BCPAP interface. It also includes detailed testing results and manufacturing plans for the device prototype. The current system has challenges in universal usability, time constraints, and patient comfort, which this project intends to address effectively. The goal of this project is to reevaluate and redesign the interface of the bubble continuous positive air pressure (BCPAP) machine’s attachment site with the infant. Due to the millions of premature neonates and thousands of …

Implementation Of Fluid Viscous Damper For 2023 Eeri Seismic Design Competition, Dalton J. Muck, Payton S. Mcgee, Payton R. Filippin, Tynan Castro

Architectural Engineering

The authors of this report were a part of the 2023 Earthquake Engineering Research Institute (EERI) student chapter for California Polytechnic State University, San Luis Obispo (Cal Poly). With thirteen other team members, they traveled to San Francisco, CA to compete in the Seismic Design Competition (SDC) hosted by EERI. The team was tasked with preparing a written proposal, design and computer analysis of the structural system, construction of two physical models, as well as creation of a poster and a presentation for a proposed mid-rise building located in the competition host city. The goal of the design of Cal …

Plc Course Development, Leonard Hernandez, Jacqueline Grace Radding

Electrical Engineering

The goal of this project is to design and construct the first lab experiment for the newly developed EE435 laboratory course. The experiment entails PLC programming to automate LED lighting in a simulated building. Starting with why PLCs are used, how to use the interface of EcoStruxure Control Expert V15.0 and practice using logic to control the dimming of a Light Emitting Diode (LED) to sustain a certain number of lumens consistent in a zone. Through the lab manual developed in this project, students will gain experience of creating logic designs using Function Block Diagram (FBD) and learn the layout …

Efficacy Of Passive Ventilation With High Exhaust Demands: A Case Study Of Cal Poly Sst, Siddarth Bokka

Construction Management

The Simpson Strong Tie Demonstration Laboratory serves as a multipurpose space allowing students at the College of Architecture and Environmental Design at California Polytechnic State University to build full scale construction projects. The building features a material storage area, a high bay for construction of full-scale projects, and a mezzanine level that houses digital fabrication equipment. However, the building was never designed to house the specific equipment currently installed on the mezzanine and ventilate the exhaust fumes from them. Rather, the building relies on passive natural ventilation that is likely ineffective at properly exhausting hazardous fumes, resulting in complaints from …

Designing A Chicken Coop For The San Luis Obispo High School Ffa Farm, Zoe King

Construction Management

This paper covers the design process by a team of students from Cal Poly to provide a chicken coop for the San Luis Obispo High School FFA Farm. The project, initiated in Summer of 2023, aimed to replace their existing temporary chicken coops with a larger, better functioning structure that could house their 10+ chickens comfortably. The paper focuses primarily on the design phase but touches briefly on material procurement and construction. Through meetings with the client, the team developed a design that met the school’s design criteria and educational needs. The design process involved collaboration and many iterations of …

Auto Adjustable Flow Regulator, Ethan Hemmerlin, Jack Dooley

Biomedical Engineering

The Auto-Adjustable Oxygen Flowmeter device is to be used in conjunction with an oxygen source or reservoir, as well as a low-flow nasal cannula apparatus. The device is applicable for patients requiring an oxygen flow rate of 0-6 L/min. Further, the device works to maintain a healthy blood-oxygen concentration of 90-94% for typical patients, as well as an 88-92% range for COPD patients who are chronic CO2 retainers. A reflective pulse oximeter will record the SpO2 concentration of the patient. The outputted SpO2 concentration will be transmitted to an internal processing PCB from which it will interact with the oxygen …

Assisted Delivery Device, Rachel Rowe, Madeliene Mumford, Jenna Eissmann, Brittany Trinh

Biomedical Engineering

Current devices used to assist in complicated births present serious risks to both the mother and the fetus, which has caused a decline in the use of these devices over the last decade. This senior project team has proposed an alternative device that interfaces with the infant’s shoulders that would decrease these risks and contribute to the decrease of unnecessary c-sections due to device inadequacy. This Statement of Work includes research on the downfalls of current devices, existing patents, customer requirements, engineering specifications, and a design plan through December of this year. The next phase of this project will include …

Tourniquet Pressure Gradient Measurement Apparatus, Luis Enrique Perez, Elsa Elizabeth Bates

Biomedical Engineering

The goal of this project was to design a device that would measure pressure gradient data across the width of an elastic and inelastic tourniquet cuff using a human limb model. The main customer requirements that were focused on were to accurately measure the pressure from a tourniquet, keep the cost down, and be easy to use. The targeted design specifications were to read pressure values ranging from 0-400 mmHg, keep the test length under 5 minutes, and to keep the cost of materials under $400. The design of the device ended up consisting of 5 IV pouches that were …

Case Study: Diesel Powered Loaders Compared To Electric Loaders In Heavy Civil Construction, Jayson Downs

Construction Management

As the construction sector evolves, the environmental consequences of greenhouse gasses have become a significant issue. Numerous contractors are transitioning to electric-powered systems, which offer more energy-efficient methods for heavy machinery, enhanced productivity, and construction equipment that meets new and improved emission standards. This paper aims to examine the viability of heavy civil construction firms transitioning from traditional diesel-powered wheel loaders to electric wheel loaders. Given the competitive and saturated market in road construction, many contractors have already started investing in electric systems. This results in cost savings in terms of fuel efficiency and operating expenses compared to conventionally fueled …

The Impact Of Culture On Construction, Vatulele Uluakiotonga Finau

Construction Management

The aim of this comprehensive exploration is to identify elements within Japanese, Islamic/Arabic, and Tongan cultures that can be implemented into construction practices in California, leveraging their unique values to enhance home design and construction. The study reveals that culture plays a pivotal role in shaping the design and construction of homes, reflecting deeply held values, traditions, and societal norms. Through qualitative research, expert interviews, and a detailed literature review, key elements defining each cultural approach to housing are elucidated. From the emphasis on privacy and natural ventilation in Japanese homes to the integration of modesty and hospitality in Islamic/Arabic …

Lemur Enclosure, Joshua Mancio, Justin Krietzberg

Construction Management

Zoo-to-You, a local wildlife conservation zoo, proposed a project to construct a new shelter for their lemurs due to the inadequacy of protection for extreme heat or cold weather of their previous enclosure. With three lemurs in residence, the zoo sought to create a spacious and insulated shelter that would provide protection from the elements while allowing connectivity to the adjacent enclosures. Situated amidst two existing circular cages with a gap in between, the project presented unique site conditions on a concrete slab. The scope of the project encompassed estimating, design, material procurement, build-out, and owner turnover, with the objective …

Effects Of The 2022 California Building Energy Efficiency Standards On New Construction In San Luis Obispo County, Christopher Hoefer

Construction Management

California released the first Building Efficiency Standards, or Energy Code, in 1976 and has updated them every three years. These standards aim at limiting the amount of energy use and greenhouse gas emissions by buildings in the state. California claims that these standards have saved consumers billions on utility bills, but there is limited information on the upfront impact the Efficiency Standards have had on new construction. This study sought to evaluate the impact that the 2022 California Building Energy Efficiency Standards had on new construction in San Luis Obispo County. Interviews were conducted with local specialty contractors in order …

Design And Construction Of A Buddy Bench For An Elementary School Play Yard, Remy N. Hickle

Construction Management

A buddy bench was designed, constructed, and installed at the Shasta Meadows Elementary School in Redding, California. A response to loneliness and bullying in schools, the buddy bench is a physical and nonverbal way students can identify the need for companionship on a school playground. By sitting on the bench, students, teachers or school administrators will see them and can come over to spend time with them. Grounded in personal connections and a deep understanding of the school's ethos, the buddy bench aims to foster empathy, inclusion, and support within the student community. Through collaborative efforts with school staff, students, …

Student Solutions For Leaf Drying: A Collaborative Approach To Enhance Moringa Production In Ghana, Daniel Desoto

Construction Management

This paper expands on a project that seeks to address the need for an updated mechanical leaf drying system for local farmers in Ghana, Africa. Working with the local organization, Moringa Connect, we were able to connect and identify potential areas of improvement within the current existing system. This project involved aspects of design, fundraising, and the construction of a rotating metal hopper. This hopper was identified as a solution for a crucial pinch point currently seen in the processing of the leaves from a wet stage to the final dry product. The design and construction process had a multidisciplinary …

Creating Content For Prison Design Course: Nordic Countries Vs. United States, Calvin Steven Clauson

Construction Management

Since 2010, prisons in Nordic countries have begun to take a very progressive approach to rehabilitating prisoners, addressing prisoners more humanely than is traditionally done in the United States. This project aims to develop course content that looks at the design elements of prisons in the United States and performs a comparative analysis with more progressive Nordic prison designs. Cal Poly’s construction management department will incorporate the developed content into one module of a co-taught course with sociology. The course will examine the ways social changes impact the construction of prisons and the social impacts of design and construction on …

Improvements Of Hybrid Ac/Dc House Prototype, Arden Abude

Electrical Engineering

This is an iteration from previous designs of the Hybrid AC/DC House with a systematic addition of a portable AC power supply unit. This iteration for the Hybrid AC/DC House is an innovation of independence for sustainable housing solutions. It will serve as an alternative for rural communities needing power to rely on self-sustainable microgrids rather than large-scale AC electric grids. The addition of a portable AC power supply would allow the microgrid to remove its reliance on AC power from the larger grid and would elevate the system to complete energy independence. The microgrid has DC power generated from …

Insights Into Cellular Evolution: Temporal Deep Learning Models And Analysis For Cell Image Classification, Xinran Zhao

Master's Theses

Understanding the temporal evolution of cells poses a significant challenge in developmental biology. This study embarks on a comparative analysis of various machine-learning techniques to classify cell colony images across different timestamps, thereby aiming to capture dynamic transitions of cellular states. By performing Transfer Learning with state-of-the-art classification networks, we achieve high accuracy in categorizing single-timestamp images. Furthermore, this research introduces the integration of temporal models, notably LSTM (Long Short Term Memory Network), R-Transformer (Recurrent Neural Network enhanced Transformer) and ViViT (Video Vision Transformer), to undertake this classification task to verify the effectiveness of incorporating temporal features into the classification …

Finite Element Analysis Of The Bearing Component Of Total Ankle Replacement Implants During The Stance Phase Of Gait, Timothy S. Jain

Master's Theses

Total ankle replacement (TAR) implants are an effective option to restore the range of motion of the ankle joint for arthritic patients. An effective tool for analyzing these implants’ mechanical performance and longevity in-silico is finite element analysis (FEA). ABAQUS FEA was used to statically analyze the von Mises stress and contact pressure on the articulating surface of the bearing component in two newly installed fixed-bearing total ankle replacement implants (the Wright Medical INBONE II and the Exactech Vantage). This bearing component rotates on the talar component to induce primary ankle joint motion of plantarflexion and dorsiflexion. The stress response …

A Sindy Hardware Accelerator For Efficient System Identification On Edge Devices, Michael Sean Gallagher

Master's Theses

The SINDy (Sparse Identification of Non-linear Dynamics) algorithm is a method of turning a set of data representing non-linear dynamics into a much smaller set of equations comprised of non-linear functions summed together. This provides a human readable system model the represents the dynamic system analyzed. The SINDy algorithm is important for a variety of applications, including high precision industrial and robotic applications. A Hardware Accelerator was designed to decrease the time spent doing calculations. This thesis proposes an efficient hardware accelerator approach for a broad range of applications that use SINDy and similar system identification algorithms. The accelerator is …

A Comparison Of Western And Eastern Soft Systems Approaches, John L. Anaya, John L. Anaya, John L. Anaya

Master's Theses

Soft System Approaches have been developed worldwide to help problem-solvers and decision-makers develop solutions to complex problems, such as aerospace systems. Soft System Approaches were designed to help lower the disorder of developing a complex system by increasing understanding of a situation. Four Soft System Approaches were investigated, two from the West and two from the East. Within the context of the paper, the West refers to thought patterns associated with thinkers and scientists in Europe and North America, and the East refers to those from and around China. The two from the West are Peter Checkland’s Soft Systems Methodology …

A Study Of Random Partitions Vs. Patient-Based Partitions In Breast Cancer Tumor Detection Using Convolutional Neural Networks, Joshua N. Ramos

Master's Theses

Breast cancer is one of the deadliest cancers for women. In the US, 1 in 8 women will be diagnosed with breast cancer within their lifetimes. Detection and diagnosis play an important role in saving lives. To this end, many classifiers with varying structures have been designed to classify breast cancer histopathological images. However, randomly partitioning data, like many previous works have done, can lead to artificially inflated accuracies and classifiers that do not generalize. Data leakage occurs when researchers assume that every image in a dataset is independent of each other, which is often not the case for medical …

Construction Software: Use, Selection, And Performance In Low-Bid Contracting, David R. Cazares

Construction Management

The qualitative research included in this study evaluates the use, selection, and perceived gaps of current construction software suits in low-bid contracting. In addition, the data aims to provide merit to the correlation between construction software use and company performance. The intended stakeholders of this study include entrepreneurs in software development and construction, along with researchers looking to gather knowledge pertaining to this niche industry. Through a Google Forms questionnaire distributed via email, participants provide insight on the current status quo. The study’s responses show clear trends in the types of software currently in use and the subsequent reasons for …