Mechanical Engineering Commons^™

Modeling Of Complex Parts For Industrial Waterjet Cleaning, Braden James

Graduate Theses and Dissertations

Industrial high-pressure waterjet cleaning is common to many industries. The modeling in this paper functions inside a collaborative robotic framework for high mix, low volume processes where human robot collaboration is beneficial. Automation of pressure washing is desirable for economic and ergonomic reasons. An automated cleaning system needs path simulation and analysis to give the operator insight into the predicted cleaning performance of the system. In this paper, ablation, the removal of a substrate coating by waterjet, is modeled for robotic cleaning operations. The model is designed to work with complex parts often found in spray cleaning operations, namely parts …

Fatigue Characteristics Of New Eco Series Aluminum 7175 Alloy, Chinh Q.L. Vu

Dissertations and Theses

In this dissertation, the fatigue characteristics of three newly developed experimental compositions for aluminum 7175, with improved mechanical strength, that uses magnesium-calcium alloy instead of pure magnesium are studied.

Specimens of each variant were fabricated and subjected to fatigue life testing, fatigue life data analysis, and observation of their fracture characteristics through optical microscopy and scanning electron microscopy (SEM), and metallography to study their grains and surface characteristics.

Fatigue life testing shows all three variants have a fatigue strength that is approaching approximately 200 MPa. ECO7175v3 is shown to have the highest fatigue strength of approximately 220 MPa at 5x10 …

Simulation Environment For Astrobee-Rings System, Tamerlan Yeleussizov

Theses and Dissertations

The thesis analyzes a flight software of a new free flying robot Astrobee, that will change the current Synchronized Position Hold Engage Reorient Experimental Satellites (SPHERES) on International Space Station (ISS). First, the main components of the flight software were examined: Robotic Operating System (ROS), Gazebo and MATLAB. During that phase, functionalities of ROS, Gazebo and MATLAB were analyzed, and it was found how these components integrate between each other to build Astrobee flying software. Next, simulation of two Astrobees performing “in-home” and “torque” maneuvers was executed. After a successful completion of simulation, results of Astrobee’s trajectory was recorded. Then, …

The Development Of A Viscoelastic Ellipsoidal Model For Use In Measuring Plantar Tissue Material Properties During Walking, Jessica Lee Deberardinis

UNLV Theses, Dissertations, Professional Papers, and Capstones

Introduction: The mechanical characteristics of the plantar tissues during walking is not well understood as most of the current research focuses on testing specific plantar regions in cadavers or while the feet of the participants are raised. In this work, it is hypothesized that a viscoelastic geometric ellipsoid model used to assess multiple structures of the foot would be accurate and robust. This model would be participant-specific and applicable to the entire stance phase of gait.

Methods: The proposed viscoelastic ellipsoid model would represent several key anatomical areas: Heel, Posterior Midfoot, Anterior Midfoot, Metatarsals 1-2, Metatarsals 3-5, Toe 1, Toe …

A Monolithic Arbitrary Lagrangian-Eulerian Finite Element Method For An Unsteady Stokes/Parabolic Interface Problem, Ian Kesler

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this thesis, a non-conservative arbitrary Lagrangian-Eulerian (ALE) method is developed

and analyzed for a type of linearized Fluid-Structure Interaction (FSI) problem in a

time dependent domain with a moving interface - an unsteady Stokes/parabolic interface

problem with jump coefficients. The corresponding mixed finite element approximation is

analyzed for both semi- and full discretization based upon the so-called non-conservative

ALE scheme. The stability and optimal convergence properties in the energy norm are

obtained for both schemes.

The Affective Perceptual Model: Enhancing Communication Quality For Persons With Pimd, Jadin Tredup

UNLV Theses, Dissertations, Professional Papers, and Capstones

Methods for prolonged compassionate care for persons with Profound Intellectual and Multiple Disabilities (PIMD) require a rotating cast of import people in the subjects life in order to facilitate interaction with the external environment. As subjects continue to age, dependency on these people increases with complexity of communications while the quality of communication decreases. It is theorized that a machine learning (ML) system could replicate the attuning process and replace these people to promote independence. This thesis extends this idea to develop a conceptual and formal model and system prototype.

The main contributions of this thesis are: (1) proposal of …

The Effects Of Bone Morphogenic Protein 2 On The Viability And Proliferation Of Dental Pulp Stem Cell Isolates, Joseph Cinelli

UNLV Theses, Dissertations, Professional Papers, and Capstones

Growth factor is an umbrella term used to describe a signaling molecule present in organisms that serves the purpose of influencing a stimulatory or inhibitory response from the target cell it acts on. Growth factors are categorized and classified by the types of tissues they act on and the cellular responses they illicit. For example, there are growth factors that act primarily in connective tissue on fibroblasts and they are aptly classified as the fibroblast growth factor family. Similarly, there is another family of growth factors that act on bone forming cells, among others, and they are known as bone …

Membrane Hull Technology Implemented Into A D-Collar Work Boat, Joshua Hagan

Theses and Dissertations

Membrane Hull Technology (MHT) was initially developed for the United States Navy Rigid-Hull Inflatable Boats (RHIB) as an alternative structure design to provide weight savings and shock mitigation. MHT accomplishes this by veering away from traditional hull design and utilizing a grid like system with an increased number of longitudinal stringers and transverse frames with a significantly lower moment of inertia when compared to traditional stringers and bulkheads. The decrease in stiffness allows for increased deflection in the hull during high load events with the added benefit of shock absorption. This technology, developed by Structural Composites Inc., has been successfully …

Feasibility Study And Hydrodynamics Of Transformable Submersible Hydrofoil Trimaran, Yipeng Pan

Theses and Dissertations

It has been the endeavor of naval architects to design innovative hull forms to address the political, socio-economic climate and sustainability around the world. It is imperative that countries be able to protect their sea lanes and coastal zones from surveillance and infiltration from hostile foreign entities. Hence there is a need to develop radically different hull form, which possess the elusive ability and are capable of high-speed. In order to fulfill the idea, the hypothesis envisioned in this thesis is: the Transformable Submersible Hydrofoil Trimaran (TSHT) as an innovative and ground breaking hull form would address the feasibility of …

Micro-Ct-Based Approaches For Quantifying The Morphology Of Pulverized Char Particles, Scott Jorgensen, Simcha L. Singer

Mechanical Engineering Faculty Research and Publications

Morphological analysis of pulverized coal char particles using two-dimensional (2-D) cross-sectional imaging has been widely employed, but its accuracy has not been adequately assessed. In this study, pulverized coal char particles are imaged in three dimensions (3-D) using high-resolution X-ray microcomputed tomography (micro-CT). Particle volume, macropore volume, and macroporosity are measured in three dimensions and analyzed as a function of distance from the particle center using averaging at each radial location. A technique for extracting each particle’s average wall thickness, another morphological parameter used for classification, is also presented based on micro-CT imaging. When applied to pulverized bituminous coal char …

Effects Of Bio-Composites In Corrugated Sandwich Panels Under Edgewise Compression Loading, Jalen Christopher Mano

Master's Theses

Present day composite sandwich panels provide incredible strength. Their largest problem, however, is early bonding failure between the core and the skin. This is due to the low bonding surface area of present cores like honeycomb. Corrugated structures could provide a remedy for this with their much larger bonding surface area. Corrugated structures have extreme mechanical properties deeming them particularly useful in aerospace and automotive applications. However, previous research has shown that the stiffness of carbon fiber causes debonding and drastic failure when used as both a core and a skin. Bio-composites have properties that could strengthen the corrugated sandwich …

Comparison Of Lqr And Lqr-Mrac For Linear Tractor-Trailer Model, Kevin Richard Gasik

Master's Theses

The United States trucking industry is immense. Employing over three million drivers and traveling to every city in the country. Semi-Trucks travel millions of miles each week and encompass roads that civilians travel on. These vehicles should be safe and allow efficient travel for all. Autonomous vehicles have been discussed in controls for many decades. Now fleets of autonomous vehicles are beginning their integration into society. The ability to create an autonomous system requires domain and system specific knowledge. Approaches to implement a fully autonomous vehicle have been developed using different techniques in control systems such as Kalman Filters, Neural …

Novel Low Temperature Cofired Ceramic Manufacturing Techniques For A Magnetron Field Emission Cathode, Daylon Michael Black

Boise State University Theses and Dissertations

Low Temperature Cofired Ceramic (LTCC) is a material system that is ideal for integrated microelectronic packaging technology, because of its rapid prototyping and easy integration of passive components such as resistors, capacitors, and conductors. LTCC’s electrical properties makes it especially suitable for high frequency applications such as magnetrons. Recently, there has been an increased demand for greater power capacities which is resolved by phase locking multiple low power (inexpensive) magnetrons together to achieve the same power as one high power (expensive) magnetron. The Vacuum Electron Devices (VED) and Ceramic Micro Electrical Mechanical Systems (CMEMS) labs at Boise State University have …

Factors Affecting Patellar Mechanics And Bone Strain In Patients With Crouch Gait, Erika Ramirez

Boise State University Theses and Dissertations

Crouch gait is a musculoskeletal impairment that results in higher than normal stresses at the patellofemoral (PF) joint that can lead to instances of anterior knee pain and loss of ambulation. The impact of commonly implemented surgical procedures to correct for crouch gait can be quantified by evaluating stresses and underlying patellar bone strain during a gait cycle. The aims of this thesis work were (1) to analyze changes in PF mechanics and patellar bone strain between pre- and postoperative conditions; (2) to quantify the variability of predicted patellar strain due to different kinematic/loading profiles or patellar material properties; and …

Capillary Penetration Method For Measuring Wetting Properties Of Carbon Ionomer Films For Proton Exchange Membrane Fuel Cell (Pemfc) Applications, Sofyane Abbou, Kazuya Tajiri, K. T. Alofari, Ezequiel F. Medici, A. T. Haug, Jeffrey S. Allen

Michigan Tech Publications, Part 1

In this work, capillary rise experiments were performed to assess the wetting properties of carbon-ionomer (CI) films. The samples were attached to a micro-balance and then immersed into liquid water to (i) measure the mass gain from the liquid uptake and (ii) estimate the (external) contact angle to water (typical value around 140°). The results showed that drying the CI films under low vacuum significantly impacted the CI film wettability. The influence of the ionomer content on the CI films’ wettability was investigated with various ionomer to carbon (I/C) ratios: 0.8, 1.0, 1.2 and 1.4. No significant variation of the …

Unmanned Aerial Power Line Surveillance Drone, Brock Arp, Wade Vine, Cameron Whigham, Lorenzo Stewart

Senior Design Project For Engineers

The purpose of our project is to provide power line workers and linemen with a safe way to inspect the power lines. Our Aircraft is an UAV that is capable of surveying 200 linear miles in a normal working shift. The aircraft will be launched/landed and operated from an F-150 pickup truck with a facilitated launch mechanism attached. The aircraft must maintain an altitude of 150-400 ft. It will be recovered via net that will extend from the truck as the plane comes in for a landing, This will eliminate the need for landing gear. The goal for this project …

A Parametric Resonator With Low Threshold Excitation For Vibration Energy Harvesting, Shahrzad Towfighian, Wei Yang

Mechanical Engineering Faculty Scholarship

A parametric resonator for vibration energy harvesting is presented. Despite large responses from parametric resonance, two major drawbacks of parametric resonance harvesters are the high threshold excitation and narrow bandwidth. We addressed these two shortcomings by adding magnetic nonlinearity to the system. The proposed vibration energy harvester consists of two piezoelectric cantilevers beams, each with a magnetic tip. By controlling the distance between the two magnets, the threshold excitation level needed to trigger the parametric resonance decreases. Combining the softening and hardening behavior of the two magnetically coupled beams increases the frequency bandwidth. In addition, the amplitude of the response …

2019 Student Steel Bridge Team, Kourtney Arena, Andrew Biglin, Brett Palmer, Nathaniel Maute, Kenneth Reiser, Jacob Dicks, Paul Kowaleski

STEM Student Research Symposium Posters

Every year AISC runs a regional and national steel bridge competition. The competition offers a chance for civil engineering students to gain valuable experience designing a bridge. In addition to this, mechanical engineering students are provided the opportunity to practice machining steel parts. For the competition, teams from participating schools are given a scenario with certain constraints to design a bridge for. At the competition, the bridges are ranked based on weight, structural efficiency, construction economy, assembly speed, deflection, aesthetics, and overall performance.

The program Risa 3D was used in order to design and perform analysis on the bridge. Using …

Thermal Management Design Tool System For Cubesat Applications, Siakrishna Reddy Kanumuru

Morehead State Theses and Dissertations

A thesis presented to the faculty of the College of Science at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science by Saikrishna Reddy Kanumuru on April 26, 2019.

Influence Of Metal Additives On Microstructure And Properties Of Amorphous Metal–Sioc Composites, Kaisheng Ming, Qing Su, Chao Gu, Dongyue Xie, Yongqiang Wang, Michael Nastasi, Jian Wang

Department of Mechanical and Materials Engineering: Faculty Publications

Strong, ductile, and irradiation-tolerant structural materials are in urgent demand for improving the safety and efficiency of advanced nuclear reactors. Amorphous ceramics could be promising candidates for high irradiation tolerance due to thermal stability and lack of crystal defects. However, they are very brittle due to plastic flow instability. Here, we realized enhanced plasticity of amorphous ceramics through compositional and microstructural engineering. Two metal–amorphous ceramic composites, Fe-SiOC and Cu-SiOC, were fabricated by magnetron sputtering. Iron atoms are preferred to form uniformly distributed nano-sized Fe-rich amorphous clusters, while copper atoms grow non-uniformly distributed nano-crystalline Cu particles. The Fe-SiOC composite exhibits high …

Cavitation Number As A Function Of Disk Cavitator Radius: A Numerical Analysis Of Natural Supercavitation, Reid Prichard

Senior Honors Theses

Due to the greater viscosity and density of water compared to air, the maximum speed of underwater travel is severely limited compared to other methods of transportation. However, a technology called supercavitation – which uses a disk-shaped cavitator to envelop a vehicle in a bubble of steam – promises to greatly decrease skin friction drag. While a large cavitator enables the occurrence of supercavitation at low velocities, it adds substantial unnecessary drag at higher speeds. Based on CFD results, a relationship between cavitator diameter and cavitation number is developed, and it is substituted into an existing equation relating drag coefficient …

The Design Of An Innovative Automotive Suspension For Formula Sae Racing Applications, Jared Darius

Senior Honors Theses

This thesis details an analytical approach to an innovative suspension system design for implementation to the Formula SAE collegiate competition. It focuses specifically on design relating to geometry, mathematical modeling, energy element relationships, and computer analysis and simulation to visualize system behavior. The bond graph approach is utilized for a quarter car model to facilitate understanding of the analytical process, then applied to a comparative analysis between two transverse half car models. The second half car model contains an additional transverse linkage with a third damper, and is compared against the baseline of the first half car model without the …

Mass Accommodation At A High-Velocity Water Liquid-Vapor Interface, J. Nie, A. Chandra, Z. Liang, P. Keblinski

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We Use Molecular Dynamics to Determine the Mass Accommodation Coefficient (MAC) of Water Vapor Molecules Colliding with a Rapidly Moving Liquid-Vapor Interface. This Interface Mimics Those Present in Collapsing Vapor Bubbles that Are Characterized by Large Interfacial Velocities. We Find that at Room Temperature, the MAC is Generally Close to Unity, and Even with Interfaces Moving at 10 Km/s Velocity, It Has a Large Value of 0.79. using a Simplified Atomistic Fluid Model, We Explore the Consequences of Vapor Molecule Interfacial Collision Rules on Pressure, Temperature, and Density of a Vapor Subjected to an Incoming High-Velocity Liquid-Vapor Interface.

Increasing Operator Skills In A Manufacturing Environment, Bobbie Lee Hubbard

Instructional Design Capstones Collection

A plastic-injection molding facility is converting many machines into more automated systems. These complex systems require higher-level skill sets than current operators have been trained in. There is a need to increase the level of competency in most, if not all, of the operators at the Facility, and create a system of levels that engages employees and encourages learning new skills to increase their position and pay.

There is a need for a clear path of compensation based on skills and actions. The Facility is currently not optimizing or maximizing their current portfolio of machines and resources, leaving an unknown …

Less-Than-Lethal Self Defense Device With An Acoustic Element, Anthony Taibi

KSU Journey Honors College Capstones and Theses

This creative capstone project involves the conception, design, and creation of a less-than-lethal self defense device with an integrated sound board to control the acoustic element. Theoretically, this device is capable of deterring potential threats without causing any serious harm or any long-term damage. When starting this project, I was very focused on sonic warfare, and how to harness the power of ultrasonic and infrasonic sound waves to subdue to target; however, I concluded that using resonant frequencies to deter a human being is too dangerous, expensive, and can have negative effects for the user of the device if used …

Concrete Crack Detection And Monitoring Using A Capacitive Dense Sensor Array, Jin Yan, Austin Downey, Alessandro Cancelli, Simon Laflamme, An Chen, Jian Li, Filippo Ubertini

Faculty Publications

Cracks in concrete structures can be indicators of important damage and may significantly affect durability. Their timely identification can be used to ensure structural safety and guide on-time maintenance operations. Structural health monitoring solutions, such as strain gauges and fiber optics systems, have been proposed for the automatic monitoring of such cracks. However, these solutions become economically difficult to deploy when the surface under investigation is very large. This paper proposes to leverage a novel sensing skin for monitoring cracks in concrete structures. This sensing skin is constituted of a flexible electronic termed soft elastomeric capacitor, which detects a change …

A High Magnification Uv Lens For High Temperature Optical Strain Measurements, Robert S. Hansen, Trevor J. Bird, Ren Voie, Katharine Z. Burn, Ryan B. Berke

Mechanical and Aerospace Engineering Faculty Publications

Digital Image Correlation (DIC) measures full-field strains by tracking displacements of a specimen using images taken before and after deformation. At high temperatures, materials emit light in the form of blackbody radiation, which can interfere with DIC images. To screen out that light, DIC has been recently adapted by using ultraviolet (UV) range cameras, lenses, and filters. Before now, UV-DIC had been demonstrated at the centimeter scale using commercially available UV lenses and filters. Commercial high-magnification lenses using visible light have also been used for DIC. However, there is currently no commercially available high-magnification lens that will allow images to …

Method And Apparatus For Fabricating Ceramic And Metal Components Via Additive Manufacturing With Uniform Layered Radiation Drying, Ming-Chuan Leu, Amir Ghazanfari, Wenbin Li, Greg Hilmas, Robert G. Landers

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A freeform extrusion fabrication process for producing three - dimensional ceramic, metal and functionally gradient composite objects, including the steps of filling a plurality of paste sources with a respective plurality of aqueous paste compositions, operationally connecting respective syringes containing respective aqueous paste compositions to a mix ing chamber, moving a first aqueous paste composition from a first respective paste source into the mixing chamber, moving a second aqueous paste composition from a second respective paste source into the mixing chamber, mixing the first and second aqueous paste compositions to define a first admixture having a first admixture composition, extruding …

An Innovative Energy Harvesting Shock Absorber System Using Cable Transmission, José Luis Olazagoitia, Lincoln Bowen, Jordi Viñolas, Javier Echávarri Otero

Artículos científicos

This paper presents an innovative design of an energy harvesting shock absorber using cable transmission called Cable-Dynamics Energy Harvesting Shock Absorber (CD-EHSA). It includes the design, modelling, bench experiments, and road tests results. Experimental tests are carried out with the CD-EHSA system in a MTS 835 machine, in order to analyze its behavior and validate the computational model of the CD-EHSA with the tests carried out on the actual component. Likewise, the paper presents the results of recovered electric power by the system during road tests at a speed between 20-30 Km/h. With four CD-EHSA installed in a Renault Twizy, …

3d Printing Robotic Arm On Linear Rails, Thomas T. Steele

Honors Theses

Typical 3D printers are bound by the printing bed volume relative to the printer frame volume. A 3D printing robotic arm set upon sliding linear rails was designed and built. The arm was 3D printed with a traditional 3D printer designed using Autodesk Inventor. This product reduces printer size while increasing bed area and reduces cost with use of 3D printed parts.