Engineering Commons^™

Three-Dimensional Laser-Assisted Printing Of Structures From Nanoparticles, Heng Pan, Chinmoy Podder, Wan Shou, Xiaowei Yu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A method for manufacturing a component comprising bombarding nanoparticles in a dispersion with a laser to transform the ligand and cause the nanoparticles to drop out of the dispersion and deposit onto a substrate; and bombarding additional nanoparticles in the dispersion with the laser to transform the ligand and cause the nanoparticles to drop out of the dispersion and deposit onto the nanoparticles previously deposited out of the dispersion.

Bibliometric Analysis On Artificial Compressibility Method Based Cfd Simulations, Bhavna Hemraj Joshi Miss, Chandrakant R. Sonawane Dr, Priyambada Bada Praharaj Mrs, Anand Kumar Pandey Dr

Library Philosophy and Practice (e-journal)

This bibliometric analysis in this paper aims to study the quantitative progress done in the artificial compressibility (AC) method-based CFD simulation and analyze its potential in solving incompressible flow simulations in computational fluid dynamics smoothly. The sector of CFD is enhancing more and more maturely due to advancements in computing architecture, numerical methods, and simulation tools. There have been various attempts to solve the pressure-velocity coupling issue in the Navier-Stokes equation. The artificial compressibility method (ACM), as opposed to pressure-correction methods, solves the incompressible equation in a non-segregated manner. With the introduction of the ACM, the system of the equation …

Splitting The Scatter: Distinguishing Marine Organisms From Oceanographic Structures Using Acoustic Monitoring, Zhen Lu, Daisuke Hasegawa, Takahiro Tanaka, David M. Spencer, Yuji Okazaki, Takeshi Okunishi

Journal of Marine Science and Technology–Taiwan

In the northwest Pacific Ocean, off the Sanriku coast of Japan, convergence between the Tsugaru Warm Current (TWC) and the cold Oyashio Current (OC) results in the formation of highly dynamic oceanographic features that promote high biodiversity and generate hotspots for a range of commercially important fisheries. However, their effects on local biodiversity over much smaller spatiotemporal scales ( < 1 km) remains unclear. With the development of acoustic technology in recent years, echo-sounders are increasingly being used to conduct high-precision fishery resource assessments and detect small-scale variability in the oceanic thermohaline structure. In this study, we conducted a simultaneous hydrographic and dual-frequency echo-sounder survey to discriminate oceanographic features and marine organisms in the TWC-OC confluence zone. Echograms of acoustic backscatter measured at 38 kHz detected similar oceanographic features that were obtained from our hydrographic survey observations, but these features were less pronounced in the 120 kHz echograms. The dynamic oceanographic structure in the TWC-OC zone returned a large amount of backscatter, making it difficult to identify marine organisms from the scatter. The frequency differences of volume backscattering strength (SV) were, however, able to distinguish oceanographic structures from zooplankton detections. Outcomes from this study highlight the difficulty of distinguishing between hydrographic and biological detections in dynamic oceanographic environments. Further research into the acoustic frequency characteristics of heterogeneous hydrographic features will help better understand how species distributions are affected, so that the acoustic method can be used to provide more accurate estimates of species abundance.

Fine-Scale Vertical Movements And Behavior Of Immature Skipjack Tuna (Katsuwonus Pelamis) Off Eastern Taiwan, Wei-Chuan Chiang, Takayuki Matsumoto, Shian-Jhong Lin, Qi-Xuan Chang, Michael K. Musyl, Yuan-Shing Ho, Fumio Ohta

Journal of Marine Science and Technology–Taiwan

Skipjack tuna are globally distributed in tropical and temperate seas but little is known about their fine-scale diving patterns and how fish size and (or) maturity influences patterns off eastern Taiwan. A total of 211 immature skipjack (36 e 47 FL cm) in the study were caught by trolling near subsurface fish aggregating devices (FADs) near Green Island (southeastern Taiwan) and were tagged with Lotek LAT-2910 archival tags. The low rate of recovery (2.4%) suggests a high post-release mortality but this low rate could also be consistent with large population sizes, dispersal, tag loss or uncooperative fishers. Five individuals were …

Evaluating The Fish Aggregation Effect Of Wind Turbine Facilities By Using Scientific Echo Sounder In Nanlong Wind Farm Area, Western Taiwan, Ting-Chieh Huang, Hsueh-Jung Lu, Jia-Rong Lin, Shih-Hsuan Sun, Kou-Wei Yen, Jing-Yi Chen

Journal of Marine Science and Technology–Taiwan

During the stages of construction and operation of the wind power facilities, fishery and fishery resources in the wind farm areas will certainly be changed greatly. One of the major concern is the aggregation effect of wind turbines facility. We use scientific echo sounder together with scuba diving to survey fish aggregations in the wind farm areas. In order to obtain echoes very near the facility, we use tilt beam angle instead of traditional vertical one. Variation of target strength varies while using tilted beam angle were discussed both by ex-situ and in-situ experiment. In ex-situ experiment, we measured TS …

Site Fidelity And Return Trips Of Visually And Olfactorily Inhibited Black Rockfish (Sebastes Schlegelii) Individuals Tracked By Acoustic Telemetry, Mitsuki Kuroda, Yoshinori Tatsu, Yuya Ueda, Hokuto Shirakawa, Kenji Minami, Kazushi Miyashita, Makoto Tomiyasu

Journal of Marine Science and Technology–Taiwan

For fish of the genus Sebastes, which have strong site fidelity, understanding the characteristics of their return trips and how their sensory cues influence behavior will be useful for conservation and resource management. Here, we conducted a behavioral tracking study for the black rockfish Sebastes schlegelii using acoustic telemetry and sensory inhibition. We compared aspects of the return process for individuals in a control group (CNT), and fish in blind (BLD) and olfactory inhibition (OLF) conditions. Nine individuals were released 850 m from the fishing site, and all of them returned. However, the time taken to complete the return varied, …

Geospatial And Acoustic Application In An Artificial Reef Site Of South Korea, Myounghee Kang, Rina Fajaryanti, Kyounghoon Lee, Eun-A Yoon, Woo-Seok Oh, Eunbi Min, Young-Jae Shin, Yong-Suk Choi, Byung-Ho Yi, Hui Zhang, Doojin Hwang

Journal of Marine Science and Technology–Taiwan

Artificial reefs are important since they provide additional habitat leading to increasing abundance and biomass of marine biota. In a Bukchon artificial reef, Jeju Island, South Korea, environment data, artificial reef properties, and acoustic data in four seasons were integrated to visualize and examine their connections using a geographic information system (GIS). As a result, regarding the spatial and temporal distributions of fishes, January had the lowest Nautical Area Scattering Coefficient (NASC, m2/nm2) and June had the highest NASC, and relatively high NASC was observed from 5 to 30 m deep throughout seasons. The influential circle (effective distance from reef) …

Design Of An Automatic Fish Processing Line Using Machine Learning, Sangam Mainali

Master's Theses

This thesis presents an approach to automatic fish processing in the fishing industry using artificial intelligence. Using transfer learning approach (VGG16 model), convolutional neural network (CNN), and image processing, this thesis demonstrates the series of steps from intake of fishes, chopping of head and tail to collecting the body parts of fishes separately thus making it ready for post-processing or direct packaging as per the industrial and consumer needs. To present the idea of the classification of fishes, we have considered five different fishes and one shrimp, altogether six classes. After the classification, the fishes are sorted out according to …

Lamin A/C Is Dispensable To Mechanical Repression Of Adipogenesis, Matthew Goelzer, Gunes Uzer

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Mesenchymal stem cells (MSCs) maintain the musculoskeletal system by differentiating into multiple lineages, including osteoblasts and adipocytes. Mechanical signals, including strain and low-intensity vibration (LIV), are important regulators of MSC differentiation via control exerted through the cell structure. Lamin A/C is a protein vital to the nuclear architecture that supports chromatin organization and differentiation and contributes to the mechanical integrity of the nucleus. We investigated whether lamin A/C and mechanoresponsiveness are functionally coupled during adipogenesis in MSCs. siRNA depletion of lamin A/C increased the nuclear area, height, and volume and decreased the circularity and stiffness. Lamin A/C depletion significantly decreased …

Laminar Flow Face Shield, Julia Carlson, Peter Hunt, Jomil Aquipel, Becky Lu

Mechanical Engineering

The scope of this project was to design a personal protective equipment (PPE) that protects the wearer from SARS-CoV-2 without inhibiting communication and was comfortable to wear for long periods of time. SARS-CoV-2, commonly known as COVID-19, is a contagious respiratory virus that spreads through droplets produced when someone who is infected by the virus coughs, sneezes, or talks. These droplets may land on the mouths or noses of nearby people or may be inhaled in the lungs, infecting those who come in contact with the virus. The current guidelines to help slow the spread of COVID-19 are to wear …

Cnc Feed Drive Control, Ryan J. Funchess, Caleb P. O'Gorman, Nick J. Desimone, Juan M. Majano, Samuel K. Wong

Mechanical Engineering

This document serves as the Final Design Report (FDR) for a senior project developed by our team: four senior Mechanical Engineering students and one computer engineering student at California Polytechnic State University, San Luis Obispo (Cal Poly). While the project was completed for, and sponsored by, Professor Simon Xing of Cal Poly, the remainder of the university’s controls professors will be indirectly benefited from this project. Our goal was to design and implement a functional CNC Feed Drive to be used for educational demonstrations and data collection. This document discusses our early product research and benchmark goals, which established constraints …

Sustainable Tiny Home, Abigail Jessica Jones, Vince John Bugni, Sean Robert Paddy, Cameron Michael Gross

Mechanical Engineering

As housing prices and environmental concerns continue to increase, many people are looking for cheaper and more sustainable ways to live. A solution to both problems is building homes with smaller footprints which incorporate renewable energy and water-reclamation systems. In addition, adding a roof pond system to the dwelling also reduces the need for heating and cooling. The roof pond system uses a water bladder on the roof which acts as a heat-sink and moveable insulation panels. This document contains the process for our final design along with results from testing the verification prototype.

Nasa Micro-G Next Challenge: Sample Container Dispensing Device, Kristin G. Kraybill-Voth, Kelsey L. Mickelson, Oscar D. Popravka

Mechanical Engineering

This Final Design Review (FDR) report outlines a Cal Poly San Luis Obispo senior design project developing a sample container dispensing device for NASA Johnson Space Center’s Micro-g NExT design challenge, a competition for university students. NASA aims to bring the first woman and next man to the moon through the Artemis missions beginning in 2024. The Micro-g NExT 2021 challenges focus on developing equipment which will support the Artemis mission, where Astronauts will conduct extensive geological sampling to further the scientific understanding of the moon. Our team designed, built, and tested a device that holds sample bags as they …

Bull Outdoor Products - Electric Grill, Sofie M. Groberman, Makai J. Baker, James T. Andrews

Mechanical Engineering

Our senior design project team designed, assembled, and tested an outdoor electric grill. The sponsor for our project is Bull Outdoor Products, a high-end outdoor kitchen set, pizza oven, and grill company. We met with our sponsor to discuss project expectations and important product characteristics. We also researched the barbecue market and its customers to determine what grill characteristics are the most important. We learned which engineering specifications needed to be tested and outlined what our goals and overall objectives for this project are. With our background research and overall objectives in mind, we came up with different solutions through …

Adapted Tricycle 2021, Carolyn Graven, Daniel Coleman, Sebin Cho, Farhan Khan

Mechanical Engineering

This document describes and outlines the details of the senior project completed by a team of four mechanical engineering students in their final year at California Polytechnic State University, San Luis Obispo. The team worked with Linda Wolff at California Children’s Services to reach their main goal: to create an exercise tricycle that can be used by Savannah. Savannah is a young adult, and she needs to be able to steer, brake, and power the tricycle using almost entirely her core muscles. Over the course of the project, the team worked to design and build a safe and functional tricycle …

F34 Beekeeper Assist, Kyle Ladtkow, Javier Guerra, Jose Velazquez, Ryan Heryford

Mechanical Engineering

Alejandro Jauregui is a veteran who now works as a commercial beekeeper. He lost both of his legs during his service. While his current prostheses allow him to fully complete his work, he has found that inspection of the bee boxes causes him severe hip and back pain. Bee box inspection is a critical task for beekeeping, especially since he maintains about 200 hives every day. Our senior project team was tasked with designing and building a device that would help him move the top bee box out of the way to allow for inspection. We performed preliminary research into …

Med-Drop Pill Dispenser, Cole Pike, Taylor Morris, Christopher Bruni, Jose Gomez

Mechanical Engineering

Veterans’ Affairs home care nurses currently spend anywhere from thirty minutes to two hours filling out monthly prescriptions one pill at a time to veterans who are unable to leave their homes. The goal of this project was to create an easy-to-use device that could be left at a patient’s home that nurses could use to quickly and accurately dispense medication into the patient’s monthly pill box.

Implementing A Data Acquisition System For The Training Of Cloud Coverage Neural Networks, Weston C. Montgomery

Master's Theses

Cal Poly is home to a solar farm designed to nominally generate 4.5 MW of electricity. The Gold Tree Solar Farm (GTSF) is currently the largest photovoltaic array in the California State University (CSU) system, and it was claimed to be able to produce approximately 11 GWh per year. These types of projections come from power generation models which have been developed to predict power production of these large solar fields. However, when it comes to near-term forecasting of power generation with variable sources such as wind and solar, there is definitely room for improvement.

The two primary factors that …

The Application Of Post-Hoc Correction Methods For Soft Tissue Artifact And Marker Misplacement In Youth Gait Knee Kinematics, Kaila L. Lawson

Master's Theses

Biomechanics research investigating the knee kinematics of youth participants is very limited. The most accurate method of measuring knee kinematics utilizes invasive procedures such as bone pins. However, various experimental techniques have improved the accuracy of gait kinematic analyses using minimally invasive methods. In this study, gait trials were conducted with two participants between the ages of 11 and 13 to obtain the knee flexion-extension (FE), adduction-abduction (AA) and internal-external (IE) rotation angles of the right knee. The objectives of this study were to (1) conduct pilot experiments with youth participants to test whether any adjustments were necessary in the …

Prediction Of In-Plane Stiffnesses And Thermomechanical Stresses In Cylindrical Composite Cross-Sections, Bryson M. Chan

Master's Theses

Accurate mechanical analysis of composite structures is necessary for the prediction of laminate behavior. Cylindrical composite tubes are a mainstay in many structural applications. The fundamental design of circular composite cross-sections necessitates the development of a comprehensive composite lamination theory. A new analytical method is developed to characterize the behavior of thin-walled composite cylindrical tubes using a modified plate theory. A generated numerical solver can predict properties such as axial stiffness, bending stiffness, layer stresses, and layer strains in composite tubes subjected to combined mechanical loading and thermal effects. The model accounts for the curvature by transforming and translating the …

Analytical, Numerical, And Computational Methods To Analyze The Time To Empty Open, Closed, And Variable-Topped Inverted Bottles, Callen Schwefler

Master's Theses

Recent unexpected experimental observations of the emptying of inverted bottles with perforations has generated interest in modeling and simulation of this phenomenon. It was observed that as a perforation, i.e., a small hole at the "top" of the inverted bottle, is added and enlarged, the overall emptying time first increases to a maximum value and then decreases until it reaches a lower limit. The change in emptying time is associated with a transition from jetting, where only water exits the neck, to glugging, a competition between air and water flows at the neck of the bottle.

This paper develops analytical …

Power Output Modeling And Optimization For A Single Axis Tracking Solar Farm On Skewed Topography Causing Extensive Shading, Logan J. Smith

Master's Theses

Many utility-scale solar farms use horizontal single axis tracking to follow the sun throughout the day and produce more energy. Solar farms on skewed topography produce complex shading patterns that require precise modeling techniques to determine the energy output. To accomplish this, MATLAB was used in conjunction with NREL weather predictions to predict shading shapes and energy outputs. The MATLAB models effectively predicted the sun’s position in the sky, panel tilt angle throughout the day, irradiance, cell temperature, and shading size. The Cal Poly Gold Tree Solar Farm was used to validate these models for various lengths of time. First, …

Failure Analysis Of The Ulnar Collateral Ligament For Youth Baseball Pitchers, Carlos Soto

Master's Theses

The objectives of this study were to (1) use kinetics from motion analysis and inverse dynamics to calculate the stress experienced by the ulnar collateral ligament (UCL) during a typical pitch cycle, (2) compare calculated maximum UCL pitching stresses to failure properties, and (3) investigate correlations between UCL stress with anthropometric and pitching biomechanical parameters. Prior motion analysis experiments of eighteen 10- to 11- year-old baseball pitchers throwing 10 fastballs were analyzed. Maximum internal elbow varus torques were calculated using inverse dynamics methods during a typical pitch cycle. Calculations used axial loading stress equations and maximum internal elbow varus torques …

Modeling And Control Of A Vertical Hopping Robot, Bradley Y. Kwan

Master's Theses

Single degree-of-freedom hopping robots are typically modeled as spring loaded inverted pendulums (SLIPs). This simplified model, however, does not consider the overall leg geometry, consequently making it difficult to investigate the optimized inertial distribution of the leg for agile locomotion. To address this issue, the first part of this thesis establishes an accurate mathematical model of a DC-motor-driven, two-link hopping robot where the motors are modeled as torque sources. The equations of motion for the two distinct phases of locomotion (stance and flight) are derived using the Lagrangian approach for holonomic systems. A Simulink/Stateflow model is developed to numerically simulate …

Design And Implementation Of A Modular Human-Robot Interaction Framework, Michael J. Juri

Master's Theses

With the increasing longevity that accompanies advances in medical technology comes a host of other age-related disabilities. Among these are neuro-degenerative diseases such as Alzheimer's disease, Parkinson's disease, and stroke, which significantly reduce the motor and cognitive ability of affected individuals. As these diseases become more prevalent, there is a need for further research and innovation in the field of motor rehabilitation therapy to accommodate these individuals in a cost-effective manner. In recent years, the implementation of social agents has been proposed to alleviate the burden on in-home human caregivers. Socially assistive robotics (SAR) is a new subfield of research …

Monte Carlo Stack-Up Tolerance Analysis Of The Hybrid Rf/Optical Antenna Edge Sensors, Kara Hewson

Master's Theses

The Deep Space Network (DSN), located at the Jet Propulsion Laboratory (JPL), is developing an RF/Optical Hybrid Antenna. This antenna concept will support the reception of high-bandwidth optical deep-space communications with simultaneous support of conventional RF uplink and downlink. The optical system on the antenna consists of sixty-four hexagonal mirrors positioned to form a spherical aperture. To align the mirrors, a Position Opto-Electronic Metrology Sensor (POEMS) system is used to measure the position of each mirror relative to one another. The POEMS system consists of a sender called a collimator, which sends collimated light to the receiving component, called a …

Pod Stabilization, Lane Matthew Pledger, Becca Stefanich, Ian Mccandless, Patrick Salter, Kirk Kuran

General Engineering

We were tasked by Holmes Solutions to find a way to stabilize their patented SWITCHBACK passenger gondola system. This system is a self-propelled pod that transitions smoothly between cables and rails. The main goal for this project is to dampen side-to-side swing of gondola pods using a modular stabilization system. This device must be within these constraints: it must fit within a work envelope, must be safe for user and operator, must perform a dampening effect, and must be compliant with the current system. We formulated many ideas to achieve the goal, including making the pod more aerodynamic, adding sliding …

Consumer-Ready Insulated Solar Electric Cooker, Simon Ford, Sachin Gokhale, Brendan Lynn, Richard Nguyen

Mechanical Engineering

An insulated solar electric cooker, or ISEC, converts solar energy into electricity to cook food, boil water, provide heat or even help charge batteries. In this project, the focus is an ISEC with a phase change material (PCM) that helps store heat when the solar energy input is minimal, such as after the sun has set. Although a successful ISEC already exists that utilizes PCM, this product can be improved in many ways. The specific revisions investigated in this report are the improvement of the thermal efficiency with the implementation of a vacuum-sealed outer pot, the reduction of the overall …

Interactive Physics Display: Air Cannon, Marina Smeltzer, Sydney Hosokawa, Jordan Nguyen, Jessica Ouyang

Mechanical Engineering

The San Luis Obispo Botanical Garden (SLOBG) is a non-profit organization that provides a place for visitors to connect with and explore nature. The sponsors from SLOBG sought an interactive physics display to be implemented in their children’s garden that will educate children and adult visitors about physics concepts in a welcoming and comfortable atmosphere. The research done showed that customers are looking for a “wow” factor with the display to surprise and engage them. Patents showed the design and build of interactive playground equipment. Government reports described the curriculum for the target audience and also outlined the safety precautions …

Sustainable Energy Storage, Jacob S. Grillo, Alyse C. Coonce, Jack R. Linchey, Nick P. Schnorr

Mechanical Engineering

This Final Design Review document covers the work we, students at California Polytechnic State University – San Luis Obispo, have performed in collaboration with Mr. Harish Bhutani and Dr. Mohammad Noori. The project’s intent is to create an energy storage system for off-grid and developing region applications using alternative technologies to lithium-ion battery storage. We plan to manufacture and assemble a scale model of the energy storage system to prove effectiveness and practicality. This system will store enough energy to power basic appliances and essential devices for a house or community. The chosen design direction will be a flywheel, as …