Other Mechanical Engineering Commons^™

Vibrating Flexoelectric Micro-Beams As Angular Rate Sensors, Yilin Qu, Feng Jin, Jiashi S. Yang

Department of Mechanical and Materials Engineering: Faculty Publications

We studied flexoelectrically excited/detected bending vibrations in perpendicular directions of a micro-beam spinning about its axis. A set of one-dimensional equations was derived and used in a theoretical analysis. It is shown that the Coriolis effect associated with the spin produces an electrical output proportional to the angular rate of the spin when it is small. Thus, the beam can be used as a gyroscope for angular rate sensing. Compared to conventional piezoelectric beam gyroscopes, the flexoelectric beam proposed and analyzed has a simpler structure.

Geometric Analysis Of Insect Wing Vein Network, Jacob White, Ying Hu, Sangjin Ryu, Seunghee Kim, Haipeng Zhang

Department of Mechanical and Materials Engineering: Faculty Publications

An insect wing consists of a thin membrane supported by a system of veins, and flow of blood through the system of veins is critical for maintaining healthy insect wings. Better understanding of the insect wing vein circulation requires to know how the efficiency of blood flow in an insect wing relates to the geometric shape of the vein. Our investigation of the wing vein network of a dragonfly Anax junius follows the idea of Murray’s law, which is established in the study of efficiency of the vein network and the geometric shape of the vein. Instead of using the …

Experimental Evaluation Of Heat Leak From Anti-Sweat Components Into Fresh Food And Freezer Compartments Of A Household Refrigerator., Delva Felissaint

Electronic Theses and Dissertations

Condensation beads forming on outside surfaces around a refrigerator is an undesirable byproduct driven by the cold temperature exhibited throughout the unit. To combat this issue, anti-sweat components usually in the form of electrical heaters or tubes carrying hot refrigerant, bring heat to the cold surfaces to ensure their temperatures do not drop below the dew point. Some heat produced by the anti-sweat components may transfer to the interior refrigerated compartment. The purpose of this study is to quantify how much heat from the anti-sweat components are entering the fresh food and freezer compartments and what impact that has on …

Mechanizing The Removal Of Soil Between Peach Trees Planted On Berms, Coleman Scroggs

All Theses

Armillaria root rot (ARR), primarily caused by the soilborne fungus Desarmillaria tabescens, has become the number one cause for peach tree decline in the Southeastern United States. Research has shown that planting peach trees on shallow berms and excavating the soil around the root collar two years after planting lessens the effects of ARR. However, berms make orchard operations such as pruning, thinning, and harvesting more cumbersome and cause cultural concerns as channels of water at their base can lead to erosion and the slope of the berms leads to herbicide and fertilizer runoff. The objective of this research was …

Creep Behavior Of A Ti-Based Multi-Principal Element Alloy, Benjamin Elbrecht

All Theses

Abstract

The understanding of microstructural damage mechanisms is the foundation of better understanding existing materials and future material development. There are significant challenges to measuring these damage mechanisms in-situ as continuous observation of the state of the microstructure is difficult or impossible for many experimental setups. This thesis presents a method for measuring grain boundary sliding (GBS) and local strain concentrations in-situ via a Heaviside function based algorithm. GBS is the shearing of two grains along their shared grain boundary and is a common damage mechanism in creep which presents as a discontinuity that can be measured with a Heaviside …

Aerodynamics And Vibrations Of A Helicopter Rotor Blade, Mohammad Khairul Habib Pulok

LSU New Orleans Theses and Dissertations

The nature of the aerodynamic environment surrounding a helicopter causes a significant amount of vibration to its whole body. Among different sources of vibrations, the aerodynamic loading on the main rotor blade is the major contributor. Therefore, analyzing a rotor blade's vibration characteristics and aerodynamic behavior becomes essential. The vortex characteristics and the wake surrounding a helicopter rotor blade play an important role because they affect the aerodynamic behavior of the rotor blade. An advanced mathematical and computational model of rotor wake and blade vortex gives a better understanding of the helicopter rotor dynamics. This study develops computational models of …

Octopus-Inspired Adhesive Skins For Intelligent And Rapidly Switchable Underwater Adhesion, Sean T. Frey, A. B. M. Tahidul Haque, Ravi Tutika, Elizabeth V. Krotz, Chanhong Lee, Cole B. Haverkamp, Eric J. Markvicka, Michael D. Bartlett

Department of Mechanical and Materials Engineering: Faculty Publications

The octopus couples controllable adhesives with intricately embedded sensing, processing, and control to manipulate underwater objects. Current synthetic adhesive–based manipulators are typically manually operated without sensing or control and can be slow to activate and release adhesion, which limits system-level manipulation. Here, we couple switchable, octopus-inspired adhesives with embedded sensing, processing, and control for robust underwater manipulation. Adhesion strength is switched over 450× from the ON to OFF state in <50 ms over many cycles with an actively controlled membrane. Systematic design of adhesive geometry enables adherence to nonideal surfaces with low preload and independent control of adhesive strength and adhesive toughness for strong and reliable attachment and easy release. Our bio-inspired nervous system detects objects and autonomously triggers the switchable adhesives. This is implemented into a wearable glove where an array of adhesives and sensors creates a biomimetic adhesive skin to manipulate diverse underwater objects.

Introducing Modeling To First-Year Engineering Students For Effective Implementation In The Engineering Design Process, Carolina Barriento, Juan F. Granizo

PanaSoMM

Introducing Modeling to First-Year Engineering Students for Effective Implementation in the Engineering Design Process

Carolina Barriento and Juan Francisco Granizo

Embry-Riddle Aeronautical University

Abstract

Modeling and Simulation are fundamental skills for all engineering students [1]. However, students are usually introduced to these concepts during their junior or even as late as their senior year. Our research aims at familiarizing students with Modeling and Simulation tools in their first year of engineering studies. We consider the fact that proper learning involves using long-term memory (in contrast with working memory) and this is accomplished by the gradual introduction and practice of the …

A Pilot Study On The Nanoscale Properties Of Bone Tissue Near Lacunae In Fracturing Women, Wen Qian, Roman Schmidt, Joseph A. Turner, Sue P. Bare, Joan M. Lappe, Robert R. Recker, Mohammed P. Akhter

Department of Mechanical and Materials Engineering: Faculty Publications

The goal of this study is to investigate the causes of osteoporosis-related skeletal fragility in postmenopausal women. We hypothesize that bone fragility in these individuals is largely due to mineral, and/or intrinsic material properties in the osteocyte lacunar/peri-lacunar regions of bone tissue. Innovative measurements with nanoscale resolution, including scanning electron microscope (SEM), an atomic force microscope that is integrated with infrared spectroscopy (AFM-IR), and nanoindentation, were used to characterize osteocyte lacunar and peri-lacunar properties in bone biopsies from fracturing (Cases) and matched (Age, BMD), non-fracturing (Controls) postmenopausal healthy women. In the peri-lacunar space, the nanoindentation results show that the modulus …

Microfluidic Device For Localized Electroporation, Justin Brooks, Arian Jaberi, Ruiguo Yang

Department of Mechanical and Materials Engineering: Faculty Publications

Electroporation is a common method of transfection due to its relatively low risk and high transfection efficiency. The most common method of electroporation is bulk electroporation which is easily performed on large quantities of cells yet results in variable levels of viability and transfection efficiency across the population. Localized electroporation is an alternative that can be administered on a similar scale but results in much more consistent with higher quality transfection and higher cell viability. This paper discusses the creation and use of a simple and cost-effective device using porous membrane for performing localized electroporation.

Phase Space Analysis Of Nonlinear Wave Propagation In A Bistable Mechanical Metamaterial With A Defect, Mohammed A. Mohammed, Piyush Grover

Department of Mechanical and Materials Engineering: Faculty Publications

We study the dynamics of solitary waves traveling in a one-dimensional chain of bistable elements in the presence of a local inhomogeneity (`defect'). Numerical simulations reveal that depending upon its initial speed, an incoming solitary wave can get transmitted, captured or reflected upon interaction with the defect. The dynamics are dominated by energy exchange between the wave and a breather mode localized at the defect. We derive a reduced-order two degree of freedom Hamiltonian model for wave-breather interaction, and analyze it using dynamical systems techniques. Lobe dynamics analysis reveals the fine structure of phase space that leads to the complicated …

The Dark Annulus Of A Drop In A Hele-Shaw Cell Is Caused By The Refraction Of Light Through Its Meniscus, Sangjin Ryu, Haipeng Zhang, Carson Emeigh

Department of Mechanical and Materials Engineering: Faculty Publications

Knowing the meniscus shape of confined drops is important for understanding how they make first contact and then coalesce. When imaged from the top view by brightfield microscopy, a liquid drop (e.g., corn syrup) confined in a Hele-Shaw cell, surrounded by immiscible liquid (e.g., mineral oil), had a dark annulus, and the width of the annulus decreased with increasing concentration of corn syrup. Since the difference in the annulus width was presumed to be related to the meniscus shape of the drops, three-dimensional images of the drops with different concentrations were obtained using confocal fluorescence microscopy, and their cross-sectional meniscus …

Modular Cable - Driven Surgical Robots, Carl A. Nelson, Nicholas Nelson

Department of Mechanical and Materials Engineering: Faculty Publications

A surgical robot can be configured for minimally invasive surgery ( MIS ) and other types of surgery with modular link geometry and disposable components. In some examples, the surgical robot includes a cable driver comprising at least one drive motor configured for tensioning a cable. The surgical robot includes an articulated surgical tool coupled to the drive motor by the cable. The articulated surgical tool comprises at least first and second articulated links and a joint coupling the first and second articulated links. The cable passes through the joint, and the joint comprises an elastic antagonist biased in opposition …

Gross Positioning Device And Related Systems And Methods, Mark A. Reichenbach, Shane M. Farritor

Department of Mechanical and Materials Engineering: Faculty Publications

Disclosed herein are gross positioning systems for use with robotic surgical devices to provide gross positioning of the robotic surgical devices. The gross positioning systems have a base, a first arm link operably coupled to the base, a second arm link operably coupled to the first arm link, a third arm link operably coupled to the second arm link, and a slidable coupling component slidably coupled to the third arm link.

Evaluating The Effects Of Granulated Rubber And Glass Fibers In Polymer Concrete As A Structural Material For Wafer Grinding Machines, Kevin Gabriel Kuehn, Philip Randall Streeter

Materials Engineering

Polymer concrete is a composite material used to replace cast iron and steel in wafer grinding machines for vibration damping. During the grinding and lapping processes of manufacturing silicon wafers, excessive vibrations may cause subsurface damage which requires additional polishing and reduces yield. Nine compositions containing various levels of granulated rubber and glass fibers were manufactured. CRM WRF-10 granulated rubber was examined at 0%, 5%, and 10% and Corning Cem-Fil glass fibers were added at 0%, 0.5%, and 1% by weight. Smooth-On EpoxAcast 690 epoxy resin was held constant at 16% for each composition. Crushed granite aggregate from Martin Marietta, …

Heating Lanyard To Warm Body Core, Cole Bunker, Spencer Alonge, Tyler Elsom, Matthew Hyland

Mechanical Engineering

Calculated Industries, a company that specializes in construction products headquartered in Carson City, Nevada, has sponsored the Heating Lanyard to Warm Body Core senior project. The objective of the project was to design and manufacture a body core heating device that will be used by construction workers to keep warm in cold environments. The goal is to create a device that is safe, comfortable, and temperature controllable. Our team consists of four mechanical engineering students at California Polytechnic State University, San Luis Obispo. Research was performed to analyze current products in the market, analyze how to best provide heat to …

Shallow-Water Wind Turbine Foundation, Andrew Walker, Nico Nani, James Cusanelli, Zachary Dunkelberger

Mechanical Engineering

Over the 2021-2022 academic year, we, the Shallow Water Wind Turbine Foundation senior project team, designed, manufactured, and tested a fixed bottom, sand mounted turbine foundation for the Cal Poly Wind Power Club’s Collegiate Wind Competition turbine. The foundation was restricted to certain material, installation, and geometric constraints outlined in this report, and needed to support the turbine under operating conditions including 22 m/s wind speeds. The design was analyzed using primarily a bearing capacity geotechnical analysis to determine final geometry and weight. The foundation was then manufactured using welded, custom carbon steel parts.

The foundation was inspected for geometric …

Mono Ski Trainer, Alexander Scott Hinerman, Shayla Anne Schoensee, Carson Rinkenberger, Barrett L. Osborne

Mechanical Engineering

The intent of this Final Design Report document is to provide the final design of a mechanical engineering senior project to our client and user Ethan Scott. The aforementioned project is a mono ski at-home trainer carried out by a group of students attending California Polytechnic State University, San Luis Obispo over one academic year. This document contains the previously shared reports Statement of Work (SOW), Preliminary Design Review (PDR), and Critical Design Review (CDR) that provide background and details of our team’s design process to reach our final design. The as-built design and evaluation is described in the Final …

Bongoties Tying Machine Design, Zachary Stednitz, Tori Bornino, Jackson Mclaughlin, Shea Charkowsky

Mechanical Engineering

BongoTies are a reusable tool for cable management or general fastening, consisting of a strong rubber band attached to a bamboo pin. BongoTies is a company founded by our sponsor Tim Petros that sells its product on a variety of popular shopping sites, such as Amazon and eBay. Currently, the assembly process is to hand-tie the rubber band to the pin for every BongoTie. This is too slow to keep up with demand, requires a skilled worker with good dexterity, and can cause pain or injury if the rubber band snaps back onto the worker’s fingers. In this senior project …

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

Mechanical Engineering

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