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Full-Text Articles in Mechanical Engineering

Cam And Design For Manufacturing: Developing A Project-Based Learning Course, Stephen Pierson May 2024

Cam And Design For Manufacturing: Developing A Project-Based Learning Course, Stephen Pierson

Mechanical Engineering Undergraduate Honors Theses

To effectively serve student career success, mechanical engineering programs must teach students how to account for manufacturing considerations in design. Despite this, manufacturing education is a glaring area of need in current engineering curricula. In fact, basic manufacturing knowledge is one of the only hard skills consistently ranked as one of the greatest weaknesses of mechanical engineering hires in surveys of industrial employers over the last few decades. Without radically changing departmental curriculum to include more emphasis on design-build projects, one solution to combat this is to incubate a lab course in mechanical engineering programs in which undergraduates would practice …


The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough May 2024

The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough

Mechanical Engineering Undergraduate Honors Theses

Mechanical Exfoliation of Graphene is an often-overlooked portion of the fabrication of quantum devices, and to create more devices quickly, optimizing this process to generate better flakes is critical. In addition, it would be valuable to simulate test pulls quickly, to gain insight on flake quality of various materials and exfoliation conditions. Physical pulls of graphene at various temperatures, pull forces, and pull repetitions were analyzed and compared to the results of ANSYS simulations, solved for similar results. Using ANSYS’ ability to predict trends in exfoliations, flake thickness and coverage using stress and deflection analyses were investigated. Generally, both strongly …


Finite Element Analysis Of The Bearing Component Of Total Ankle Replacement Implants During The Stance Phase Of Gait, Timothy S. Jain Mar 2024

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 Study On High-Frequency Bending Fatigue, Microhardness, Tensile Strength, And Microstructure Of Parts Made Using Atomic Diffusion Additive Manufacturing (Adam) And Additive Friction Stir Deposition (Afsd), Hamed Ghadimi Feb 2024

A Study On High-Frequency Bending Fatigue, Microhardness, Tensile Strength, And Microstructure Of Parts Made Using Atomic Diffusion Additive Manufacturing (Adam) And Additive Friction Stir Deposition (Afsd), Hamed Ghadimi

LSU Doctoral Dissertations

This dissertation reports the findings of several studies on the mechanical and microstructural properties of parts made using atomic diffusion additive manufacturing (ADAM) and additive friction stir deposition (AFSD). The design of a small-sized bending-fatigue test specimen for an ultrasonic fatigue testing system is reported in Chapter 1. The design was optimized based on the finite element analysis and analytical solution. The stress–life (S–N) curve is obtained for Inconel alloy 718. Chapter 2 presents the findings of ultrasonic bending-fatigue and tensile tests carried out on the ADAM test specimens. The S-N curves were created in the very high-cycle fatigue regime. …


Depressurization Characteristics Of Steam-Based Reciprocating Vacuum Pump, Hongling Deng Dec 2023

Depressurization Characteristics Of Steam-Based Reciprocating Vacuum Pump, Hongling Deng

Dissertations

This dissertation introduces a novel vacuum technology that leverages low-pressure saturated steam and cooling-controlled condensation, offering an efficient way to utilize low-grade thermal energy sources like waste heat, steam, or solar energy. At the heart of this technology is a unique duo-chamber vacuum pump system, featuring a reciprocating piston and a heat-conductive wall, designed to generate a vacuum through steam-condensation and cooling processes.

The core of this research lies in developing and validating mechanistic models for the steam-condensation depressurization process, a complex phenomenon involving phase change and transport mechanisms. Prior to this work, these mechanisms were not sufficiently modeled or …


Modeling Of Asphalt Concrete For Cross-Anisotropic Visco-Elasticity And Heterogeneity, Zafrul Hakim Khan Dec 2023

Modeling Of Asphalt Concrete For Cross-Anisotropic Visco-Elasticity And Heterogeneity, Zafrul Hakim Khan

Civil Engineering ETDs

Asphalt Concrete (AC) is a cross-anisotropic viscoelastic material. This study has developed a methodology to backcalculate the cross-anisotropic properties of the AC layer from the Falling Weight Deflectometer (FWD) sensor and pavement response data from embedded sensors inside a pavement section. This study has also developed a two-way coupled Multiscale Finite Element Model (MsFEM) with Phase Field Fracture (PFF) to study the microstructural heterogeneity and damage of the AC layer based on the actual field loadings. A Finite Difference Time Domain (FDTD) and Machine learning-based backcalculation algorithm were developed to determine the layer thickness and dielectric constant from air-coupled Ground …


Numerical Investigation Of Subglottal Stenosis Effects On Human Voice Production, Dariush Bodaghi Dec 2023

Numerical Investigation Of Subglottal Stenosis Effects On Human Voice Production, Dariush Bodaghi

Electronic Theses and Dissertations

This dissertation aimed to advance knowledge of how subglottal stenosis impacts voice production physiology. An in-house fluid-structure-acoustic interaction approach based on the hydrodynamic/acoustic splitting technique was employed. This technique was rigorously verified for simulating phonation by matching the acoustic behavior to a compressible flow solver for phonation-relevant geometries. Simulations of an idealized 2D vocal tract model demonstrated the effects of supraglottal acoustic resonance on vocal fold kinematics and glottal flow waveform. Results showed that the acoustic coupling between higher harmonics and formats generated pressure oscillations, modifying vocal fold dynamics and glottal flow rate.

A major novelty was the incorporation and …


Cnc Retrofits, Fabian Samano, Murat Askin, Daniel Lonczak, Zane Campise Dec 2023

Cnc Retrofits, Fabian Samano, Murat Askin, Daniel Lonczak, Zane Campise

Mechanical Engineering

The Boxford CNC Lathe is a machine used for educational purposes. The goal of the CNC Retrofits project is to improve the Boxford MT2’s performance and functionality to enable Mr. Lonczak to manufacture customized ballpoint pens. Within this Final Design Review (FDR) document, we present design updates since the CDR and implementation/assembly techniques. This work culminates in a solution to Mr. Lonczak’s needs which is analyzed in three subsystems: main control, spindle position tracking, and user interface. Within this report, we show the results of each subsystem’s verification process. These results prove that the design concept was met by describing …


Deep Reinforcement Learning For The Design Of Structural Topologies, Nathan Brown Dec 2023

Deep Reinforcement Learning For The Design Of Structural Topologies, Nathan Brown

All Dissertations

Advances in machine learning algorithms and increased computational efficiencies have given engineers new capabilities and tools for engineering design. The presented work investigates using deep reinforcement learning (DRL), a subset of deep machine learning that teaches an agent to complete a task through accumulating experiences in an interactive environment, to design 2D structural topologies. Three unique structural topology design problems are investigated to validate DRL as a practical design automation tool to produce high-performing designs in structural topology domains.

The first design problem attempts to find a gradient-free alternative to solving the compliance minimization topology optimization problem. In the proposed …


Modular Composite Sandwich Structures For Thermal And Structural Retrofitting Of Existing Buildings, Marc Al Ghazal Dec 2023

Modular Composite Sandwich Structures For Thermal And Structural Retrofitting Of Existing Buildings, Marc Al Ghazal

Masters Theses

Around 40% of global energy consumption and 30% of worldwide carbon dioxide (CO2) emissions are attributed to buildings. Most of this consumption is dedicated to ensuring thermal comfort. The goal of this research was to develop and field validate retrofit solutions to improve the energy efficiency of buildings. Exterior cladding panels were designed and tested to ensure adequate thermal and structural performance. Sandwich panels (glass fibers reinforced polymer (GFRP) skins and polymeric foam cores) were fabricated using the vacuum assisted resin transfer molding (VARTM) process. Extruded polystyrene (XPS) and polyurethane (PU) foams were compared as core materials through a series …


Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm Dec 2023

Deep Ocean Vehicle Applications And Modifications, Nichole "Nikki" T. Arm

Master's Theses

This project had two primary goals: (1) to explore opportunities to further a deep-ocean vehicle’s reach using alternative pressure spheres, and (2) to implement an existing deep-ocean vehicle (lander) in active scientific research.

I gained a greater understanding of the limitations and design choices made for existing pressure spheres using Finite Element Analysis (FEA). My simplified FEA model predicted sphere failure for the existing 30% Fiber Glass 70% Nylon injection molded spheres at an external pressure of 3,954psi or 2,690m ocean-depth (only a 7.38% error compared to the tested minimum failure depth), so I determined it a valid model. I …


Discourse Analysis In Engineering: Investigating Patterns In Brainstorming Conversations, Aimee Chiem Dec 2023

Discourse Analysis In Engineering: Investigating Patterns In Brainstorming Conversations, Aimee Chiem

Master's Theses

Brainstorming is a critical part of the engineering design process and can have a significant impact on the outcomes of the overall project. While research has studied the outcomes of brainstorming and the ideas that teams generate, the role that language and conversation play in these activities is still relatively underexplored. Observing the different ways people use specific types of discourse can reveal how conversations can affect brainstorming itself. To that end, this research aims to answer the following questions:

1) What are the different kinds of discursive moves that students make during engineering brainstorming activities?

2) What patterns or …


Deep Learning And Generative Ai Approaches For Automated Diagnosis And Personalized Treatment: Bridging Machine Learning, Medicine, And Biomechanics In Predicting Tissue Mechanics And Biomaterial Properties., Yasin Shokrollahi Dec 2023

Deep Learning And Generative Ai Approaches For Automated Diagnosis And Personalized Treatment: Bridging Machine Learning, Medicine, And Biomechanics In Predicting Tissue Mechanics And Biomaterial Properties., Yasin Shokrollahi

Theses and Dissertations

Machine learning, particularly deep neural networks, has demonstrated significant potential in predicting high-dimensional tasks across various domains. This work encompasses a detailed review of Generative AI in healthcare and three studies integrating machine learning with finite element analysis for predicting biomechanical behaviors and properties. Initially, we provide a comprehensive overview of Generative AI applications in healthcare, focusing on Transformers and Denoising Diffusion models and suggesting potential research avenues to address existing challenges.

Subsequently, we addressed soccer-related ocular injuries by combining finite element analysis and machine learning to predict retinal mechanics following a soccer ball hit rapidly. The prediction errors are …


Enhancing Human Key Point Identification: A Comparative Study Of High-Resolution Vicon Dataset And Coco Dataset Using Bpnet, Bibash Lama Aug 2023

Enhancing Human Key Point Identification: A Comparative Study Of High-Resolution Vicon Dataset And Coco Dataset Using Bpnet, Bibash Lama

Masters Theses

Accurately identifying human key points is crucial for various applications, including activity recognition, pose estimation, and gait analysis. This study presents a high-resolution dataset created using the VICON motion capture system and three differently oriented 2D cameras, that can be used to train different neural networks for estimating the 2D key joint positions of the person from the 2D images or videos. The participants in the study included 25 healthy adults (17 males and 8 females) performing normal gait movements for about 2 to 3 seconds. The VICON system captured 3D ground truth data, while the three 2D cameras collected …


An Automated, Deep Learning Approach To Systematically & Sequentially Derive Three-Dimensional Knee Kinematics Directly From Two-Dimensional Fluoroscopic Video, Viet Dung Nguyen Aug 2023

An Automated, Deep Learning Approach To Systematically & Sequentially Derive Three-Dimensional Knee Kinematics Directly From Two-Dimensional Fluoroscopic Video, Viet Dung Nguyen

Doctoral Dissertations

Total knee arthroplasty (TKA), also known as total knee replacement, is a surgical procedure to replace damaged parts of the knee joint with artificial components. It aims to relieve pain and improve knee function. TKA can improve knee kinematics and reduce pain, but it may also cause altered joint mechanics and complications. Proper patient selection, implant design, and surgical technique are important for successful outcomes. Kinematics analysis plays a vital role in TKA by evaluating knee joint movement and mechanics. It helps assess surgery success, guides implant and technique selection, informs implant design improvements, detects problems early, and improves patient …


Development Of A Soft Robotic Approach For An Intra-Abdominal Wireless Laparoscopic Camera, Hui Liu Aug 2023

Development Of A Soft Robotic Approach For An Intra-Abdominal Wireless Laparoscopic Camera, Hui Liu

Doctoral Dissertations

In Single-Incision Laparoscopic Surgery (SILS), the Magnetic Anchoring and Guidance System (MAGS) arises as a promising technique to provide larger workspaces and field of vision for the laparoscopes, relief space for other instruments, and require fewer incisions. Inspired by MAGS, many concept designs related to fully insertable magnetically driven laparoscopes are developed and tested on the transabdominal operation. However, ignoring the tissue interaction and insertion procedure, most of the designs adopt rigid structures, which not only damage the patients' tissue with excess stress concentration and sliding motion but also require complicated operation for the insertion. Meanwhile, lacking state tracking of …


Influence Of Swirl And Turbulence In The Particle Removal Using Fog In A Pipe Flow, Nisarg T. Patel Aug 2023

Influence Of Swirl And Turbulence In The Particle Removal Using Fog In A Pipe Flow, Nisarg T. Patel

All Theses

Fog-and-tube scrubbers are employed to remove harmful ultrafine aerosols, such as Diesel particulate matter (DPM), from an airflow. The underlying principle of this removal process involves enlarging the aerosol particles by coagulating them with fog drops, which are subsequently eliminated through inertial impaction onto the tube wall. Previous research conducted by Tabor et al. (2021) demonstrated an increase in scavenging of ultrafine DPM particles, ranging from 11.5 nm to 154 nm, by as large as 45% over the no fog case. This finding is crucial in addressing the challenges associated with conventional filtration methods for capturing ultrafine particles.

The present …


Theoretical And Experimental Study Of Active Magnetic Bearing Control Integrated On Bently's Rotor Kit, Arturo Mario Flores Aug 2023

Theoretical And Experimental Study Of Active Magnetic Bearing Control Integrated On Bently's Rotor Kit, Arturo Mario Flores

Master's Theses

This thesis focuses on the comprehensive study of controlling a customized Active Magnetic Bearing (AMB) installed on Bently Nevada’s RK4 rotor kit in Cal Poly’s Vibrations and Rotordynamics Lab. The AMB was uniquely designed and manufactured by a Cal Poly senior project team to fit Bently’s rotor kit and the results of this research are distinctive to the custom system. To achieve practical functionality of the AMB system, we designed a controller a Virtual Instrument (VI) using the National Instrument software, LabVIEW. From the experimental study, we calibrated the programming to find unknown parameters of the AMB system and validated …


Design Of Machine Tool Cross Beam Using Metal Big Area Additive Manufacturing, Tyler Poon Aug 2023

Design Of Machine Tool Cross Beam Using Metal Big Area Additive Manufacturing, Tyler Poon

Masters Theses

The modern world would not be what it is now without machine tools. Advances in materials and processes, such as carbon fiber and additive manufacturing (AM), enable the design space for machine tool components to expand. However, machine tool components require accurate geometry, which is not available from parts produced by metal Big Area Additive Manufacturing (mBAAM). This project outlines the process in which a traditionally manufactured machine tool component, a welded box structure on an existing machine tool, was redesigned to be made using mBAAM. The goal was to design a structure that was printable using the MedUSA system …


Modeling, Control, And Hardware Development Of A Thrust-Vector Coaxial Uav, Andrew North Jul 2023

Modeling, Control, And Hardware Development Of A Thrust-Vector Coaxial Uav, Andrew North

Doctoral Dissertations and Master's Theses

This thesis introduces a unique thrust vector coaxial unmanned aerial vehicle (UAV) configuration and presents a comprehensive investigation encompassing dynamics modeling, hardware design, and controller development. Using the Newton-Euler method, a dynamic model for the UAV is derived to gain in-depth insights into its fundamental flight characteristics. A simple thrust model is formulated and modified by comparing it with data obtained from vehicle testing. The feasibility of manufacturing such a vehicle is assessed through the development of a hardware prototype. Finally, a linear state feedback controller is designed and evaluated using the non-linear dynamics model. The results demonstrate successful validation …


Aeroponic System Optimization For Butterhead Lettuce Growth And Future Sustainability Using Flow Blurring Atomization, Taylor J. Johnson Jul 2023

Aeroponic System Optimization For Butterhead Lettuce Growth And Future Sustainability Using Flow Blurring Atomization, Taylor J. Johnson

Doctoral Dissertations and Master's Theses

The global population has grown by 6 billion people over the last century and is trending toward 9.7 billion people by the year 2050. Agriculture accounts for 70% of global fresh water usage. Technology must be developed to accommodate the increase of food production demanded by the growing global population and the subsequent increase in water usage. Aeroponic technology is a water-efficient vertical farming technology that can reduce water usage by 90% by suspending plant roots in air within a controlled chamber and supplying atomized droplets of a water-nutrient solution directly to the roots.

This study simultaneously tests six droplet …


Sky Survey Radio Telescope, Jack E. Mcguigan Jun 2023

Sky Survey Radio Telescope, Jack E. Mcguigan

Electrical Engineering

This document outlines the design of a radio telescope designed to perform hydrogen line sky surveys. The telescope produces radio images mapping the intensity and relative velocities of hydrogen concentrations to their sky coordinates. Over the course of a day, the telescope images the regions of space visible to it, allowing sky survey imagery to be updated daily. Sky survey images are comprised of an array of pixels corresponding to specific sky coordinates. Each 8-bit RGB pixel contains information on the concentrations of hydrogen in the brightness and relative velocity in the color. Radio images mapping the concentrations and velocities …


Baja Sae Semi-Active Suspension, Cameron Paul Jones, Ethan Jacobi Mikel, Joshua Macguire Wright, Aditya Garg Jun 2023

Baja Sae Semi-Active Suspension, Cameron Paul Jones, Ethan Jacobi Mikel, Joshua Macguire Wright, Aditya Garg

Mechanical Engineering

This document outlines the design and justification for the final design of the Baja SAE Semi-Active Suspension Senior Project. The goal of the project was to build a base valve that can adjust suspension damping rates on the fly. This document details the ideation, design, manufacturing, design verification results, and detailed drawing package for the project. Additionally, this document includes information regarding the pressure drop calculator, O-ring calculations, and CAD. The manufacturing processes used to create the valve and the testing and evaluation of the valve are included as well. Finally, the methods that were used to manage this project …


Headlamp/Bike Light Damping System, Ethan Reece Clark, Alec Stonehouse, Omeed Ostry, Mitchel Anderson Jun 2023

Headlamp/Bike Light Damping System, Ethan Reece Clark, Alec Stonehouse, Omeed Ostry, Mitchel Anderson

Mechanical Engineering

The task for this project is to design a headlamp and/or bike light that absorbs the impact shocks from the user’s actions. The user that the system is being designed for may be riding a bike or running on a trail in the evening or early in the morning where the light needs to be stabilized and their path must be illuminated. This report presents the final design chosen after months of prototyping and design iteration. It encompasses the system design, design verification through testing, implementation, future recommendations, and lessons learned throughout the process. The chosen design utilizes a fully …


Prove Primary Battery Structure, John D. Burkhart, Andy Mccormick, Ryan Yu, Soren Barclay Jun 2023

Prove Primary Battery Structure, John D. Burkhart, Andy Mccormick, Ryan Yu, Soren Barclay

Mechanical Engineering

In conjunction with Prototype Vehicle (PROVE) Laboratory, our group designed, manufactured, and tested a prototype structure to house the battery boxes for PROVE’s endurance vehicle. Our structure was designed to support the batteries during normal use, and in the event of a front crash. Our design is comprised of a secondary composite box to house the battery boxes, a bottom plate to affix the secondary box to the chassis floor, a horizontal plate fastened to the chassis, and a brace structure welded to the chassis. From the outset, we chose to use a secondary box, the primary battery boxes must …


Programmable Vibration Table Retrofit With Eagle Medical, Jonathan Ilagan, Madhav Asok, Max Lewter Jun 2023

Programmable Vibration Table Retrofit With Eagle Medical, Jonathan Ilagan, Madhav Asok, Max Lewter

Biomedical Engineering

This project aimed to repair and upgrade a vibration table used for package testing for the sponsor, Eagle Medical - a medical packaging and sterilization company based in Paso Robles, California. The current vibration table is not programmable and lacks circuit diagrams, making it difficult to repair. In addition, it is not functional due to internal circuitry issues and power requirements. To address these issues, the team will implement several upgrades to improve the product and allow for better random cyclic vibration testing. A full assessment of the existing vibration table will be conducted to ensure the viability of these …


The Center For Centering Dome, Olek Piechaczek, Ryan M. Scharf Jun 2023

The Center For Centering Dome, Olek Piechaczek, Ryan M. Scharf

Architectural Engineering

The Center for Centering seeks to create a large-scale healing center, conducive to individual centering of the mind and body. This mobile installation provides a relaxing, enclosed space while still maintaining a connection to the outdoors. The clients liked the idea of having a pop-up installation that could be easily set up as a touring display. With a deadline for installation looming in June 2022, a team of students had five months to design and manufacture the structure.

In winter 2022, the students developed custom geometry to minimize the number of individual parts and built a ¼ scale model of …


Implementation Of Topology Optimization Into The Mechanical Design Process, Nolan Clapp Jun 2023

Implementation Of Topology Optimization Into The Mechanical Design Process, Nolan Clapp

Master's Theses

Topology Optimization is a lightweighting method based on finite element analysis that produces a part with optimum material distribution in the design space. Results from topology optimization often have organic shapes and curves that are difficult if not impossible to machine with traditional subtractive manufacturing methods. This paper analyzes the implementation of the Solidworks® Topology Optimization add-in into the mechanical design process and discusses required postprocessing to ensure manufacturability of the optimized part though a case study on two example parts. Results of traditional optimization, topology optimization and “selective” optimization (optimization using the results from topology optimization to selectively remove …


The Development Of A Primer Payload With Microparticles For Uti Pathogen Identification Using Polythymidine- Modified Lamp Primers In Droplet Lamp, Jonas Otoo May 2023

The Development Of A Primer Payload With Microparticles For Uti Pathogen Identification Using Polythymidine- Modified Lamp Primers In Droplet Lamp, Jonas Otoo

KGI Theses and Dissertations

Nucleic acid amplification tests (NAATs) are among the diagnostic tests with the highest sensitivity and specificity. However, they are more complex to develop than other diagnostic tests such as biochemical tests and lateral flow immunoassay tests. Polymerase chain reaction (PCR) is the gold standard for NAATs. PCR requires thermal cycling to achieve clonal amplification of the target pathogen DNA for diagnosis. Thermal cycling poses a challenge in the development of PCR diagnostics for point-of-care (POC) settings. Loop-mediated isothermal amplification (LAMP) offers an isothermal method for NAATs diagnostics. The advancement of the microfluidics field significantly enhances the development of LAMP diagnostics …


Crafting Comfort: The Design And Production Of A High-End Poolside Lounge Chair, John Hollis Tackett, Robert Griffis May 2023

Crafting Comfort: The Design And Production Of A High-End Poolside Lounge Chair, John Hollis Tackett, Robert Griffis

Honors Theses

This report focuses on the development, design, and manufacturing of the Adjustable Lounge Chair, a high-end poolside lounge chair created to address un-met customer demand in the market. The investigation began with a market analysis to identify sought-after features not currently offered by competitors' products. This analysis drove the design of the chair, which was developed using CAD software, followed by the construction of a physical prototype to validate the concept.

The chair's innovative features include adjustable lumbar support and chair height, as well as a removable face-piece that enables users to comfortably lie prone without straining their necks. These …