Mechanical Engineering Commons^™

Comparative Analysis And Dynamic Response Of Abs Under Uv Light Degradation Using Shock Tube, Greer Lauber

Honors Theses

The purpose of this study was to examine the dynamic response of acrylonitrile-butadlene-styrene (ABS) when exposed to UV light. Impact-Resistant Easy-to-Form ABS sheets were tested using a Shock Tube. Three samples were tested at no UV light exposure and three were tested after 15 days of being exposed to rapid UV degradation rays. All samples were tested at a shock wave equivalent to 400 psi. The results showed that the UV damaged samples experienced a decrease in strength and energy absorption in comparison to the non-UV damaged samples. The average peak load for the non-UV degraded was 1261.89 Newtons and …

Efficient Energy Harvesting With Applications In Vibration And Implantable Biosensors, Mohammad Atmeh

Mechanical Engineering Theses

The world has stepped into the fourth industrial revolution in many ways such as using the internet of things (IoT) in various applications, and removing the rechargeable power sources seeking for batteryless systems. Since energy is widely abundant around us and it is going to waste, numerous of recent studies have been conducted to propose sustainable solutions to harvest the free ambient power from the surrounding and convert it into electricity. Heat energy, kinetic energy, and radio waves are examples of these potentially harvestable energy sources. Mechanical vibrations represent one of the most plentiful forms of kinetic energy that can …

Leverage Topology Optimization To Maximize Structure Design Efficiency, Teng Li, Saad Aqerrout

ME 4233/6233 Fundamentals of FEA

This paper presents the topology optimization method to improve the efficiency of mechanical structure design.

Computational Mechanics Implementation Of Performance Based Testing In Massive Concrete Structures, Gabriel Y. Riveros

ME 4233/6233 Fundamentals of FEA

Most of the nation’s critical water resource infrastructures are near or have exceeded their design lives. Consequently, there is a huge need for the development of assessment procedures that will change the way dams are maintained and operated with the intent of extending the service life. This is crucial for ensuring the safety and security of our nation’s public services. The combination of advanced computational mechanics and performance based testing (PBT) methods can be used to investigate the existing conditions of large concrete structures.

Performance based testing (PBT) is a new and innovative non-destructive testing technique that we are implementing …

Comparison Of Johnson-Cook And Linear Elastic-Perfectly Plastic Material Models For Ballistic Impact Case, Logan J. Callahan, Marella Failla, Harrison Williams

ME 4233/6233 Fundamentals of FEA

In an effort to characterize the linear elastic-perfect plastic (J2) and Johnson-Cook (JC) Strengthening and Damage material models for an Aluminum target material being struck by a steel penetrator, finite element analysis (FEA) will be used to simulate the residual velocities from ballistic impacts, using various velocities of the penetrator. The object is to define the point at which the J2 material model is no longer accurate and therefore requires the use of the JC material models.

Numerical Analysis Of Taylor Impact With Various Nose Shapes, Jean C. Santiago Padilla, Erik M. Chappell

ME 4233/6233 Fundamentals of FEA

The Taylor impact test is an experimental technique used to determine dynamic material response and to validate constitutive models used in numerical simulations. It generally consists of shooting a cylinder rod of a select material against a rigid target at different velocities. After impact, the plastic deformation of the cylinder is recorded and is directly compared to numerical predictions. Another application for Taylor impact was proposed by Li et al. (2021) where the nose shape of the cylinder is modified to create different loading environments that can test electronic equipment in penetration weapons. FEA models where designed in ABAQUS/Explicit to …

Analysis Of Preload In Bolted Joints Under Impulse, Albert Dusseault

Thinking Matters Symposium

From transportation to storage to construction, bolted joints are utilized everywhere. Bolted joints in closures such as pressure vessels/tanks require a preload, or a specific amount of tightening of the bolts to seal the vessel when pressurized to avoid leaking. Low preload can result in joint loosening whereas high preload can result in yielding. Therefore, finding feasible and even better optimal values of preload is of great practical importance. In an earlier work in 1996, this problem was tackled with an exponentially decaying pressure applied on a pressure vessel closure. In the present analysis, however, the pressure variation is considered …

Molecular Dynamics Study Of Melting Behavior Of Planar Stacked Ti–Al Core–Shell Nanoparticles, Huadian Zhang, Yu Chen Su, Yiwei Han, Shan Jiang

Faculty and Student Publications

Selective laser sintering (SLS) is one of the most commonly used methods in additive manufacturing, due to its high prototyping speed and applicability to various materials. In the present work, molecular dynamics (MD) simulations were performed to study the thermodynamic behaviors of the planar stacked nanoparticles (NPs) model and explore the potential capability of the SLS process with nano-sized metal powders in the zero-gravity space environment. A multi-particle model of titanium–aluminum (Ti–Al) core–shell NP with a particle radius of 50 Å was constructed to investigate the characteristics of the melted pattern during sintering. Two patterns with different spatial densities were …

Investigating Polynominal-Fit Extrapolation For Iterative Gain Updating In A Controller, Malachi Landis

Honors Capstone Projects and Theses

No abstract provided.

Reducing Torsion In Asymmetric Structures During Earthquakes Through Active Control, Keona Lauren Banks

Honors Capstone Projects and Theses

No abstract provided.

Surface Laser Texturing Of Cocrmo Alloys, Gabriel Dharwadker

Biomedical Engineering Undergraduate Honors Theses

Artificial orthopedic implants such as hip joints suffer from excessive wear due to excess friction between the polyethylene and cobalt-chromium-molybdenum surfaces of the device. This increase in friction causes a fraction of them to give out within ten years. Therefore, to minimize the probability of this happening, recent research has been conducted regarding laser surface texturing of the cobalt-chromium-molybdenum alloy components of artificial joints. These surface textures serve to mimic the native lubrication mechanisms of cartilage in natural joints, which, in a natural joint, lowers the friction. However, the production of these laser surface textures is still a field of …

Classifying Hazardous Movements And Loads During Manual Materials Handling Using Accelerometers And Instrumented Insoles., Mitja Trkov, Duncan T Stevenson, Andrew S Merryweather

Henry M. Rowan College of Engineering Departmental Research

Improper manual material handling (MMH) techniques are shown to lead to low back pain, the most common work-related musculoskeletal disorder. Due to the complex nature and variability of MMH and obtrusiveness and subjectiveness of existing hazard analysis methods, providing systematic, continuous, and automated risk assessment is challenging. We present a machine learning algorithm to detect and classify MMH tasks using minimally-intrusive instrumented insoles and chest-mounted accelerometers. Six participants performed standing, walking, lifting/lowering, carrying, side-to-side load transferring (i.e., 5.7 kg and 12.5 kg), and pushing/pulling. Lifting and carrying loads as well as hazardous behaviors (i.e., stooping, overextending and jerky lifting) were …

Mechanistic Undrestanding Of Amorphization In Iron-Based Soft Magnetic Materials, Taban Larimian

ETD Archive

Iron-based magnetic alloys possess very good magnetic and mechanical properties. Among these alloys Fe-Si-B-based alloys show outstanding saturation magnetization and coercivity which makes them great candidates for many industrial applications. Addition of certain elements to the Fe-Si-B base is proven to improve the homogeneity and fineness of microstructure as well as enhance the magnetic behavior of these alloys. In this research work, we have studied the effect of adding copper and niobium to the Fe-Si-B base alloy. Previous studies have shown that magnetic alloys show better magnetic properties when their microstructure consists of nanocrystals embedded in an amorphous matrix. In …

Understanding Thermal Comfort Impact And Air Movement Around Open Stairs Through The Use Of Cfd Modeling, Ethan Davidson

Graduate Theses and Dissertations

The air exchange between two floors of a building has an impact on thermal comfort. The present research attempts to quantify this impact and identify the contributing factors disrupting the thermal comfort on and around stairs. Various heating and cooling scenarios were analyzed, using CFD modeling, in a simple two-story building separated by a single staircase. The research examines a single building layout with a fixed inlet and outlet configuration. In addition, the study investigated the short-term impact on thermal comfort. As a result, the duration of the simulations varies from two and half minutes to ten minutes, consistent with …

Development Of An Accelerated Life Testing Method For Reliability Assessment Of Wire Bonded Interconnects Subjected To Mechanical And Electromigratory Stresses, Whit Vinson

Graduate Theses and Dissertations

Power electronic advancement trends indicate that device power density will continue to increase as a result of increased power requirements and desired device form factor reduction in order to reduce weight and material costs and increase ease of integration into next-generation power systems. With these advancements come concerns regarding device reliability. The compounded effects of increased power density and form factor reduction in electrical conductors will yield amplified joule heating effects in addition to the already increasing device temperature profiles resulting from the incorporation of wide bandgap technology into power systems. Joule heating effects can lead to a variety of …

Ballasting System For An Autonomous Underwater Vehicle, Noura Rayes, Bahram Nassersharif, Zach Champney, Kyle Alessandro, Jason Mirandou

Senior Honors Projects

NOURA RAYES (Mechanical Engineering); Ballasting System for an Autonomous Underwater Vehicle Sponsor: Bahram Nassersharif (Mechanical Engineering)

Over the last year, our Mechanical Engineering Capstone team, Nautilus, has been working to design a ballasting system for various Autonomous Underwater Vehicles (AUVs) sponsored by Raytheon Technologies. Common AUV systems are used for a wide range of applications from environmental monitoring, oceanic exploration, to data collection. AUVs also have many technical advantages that make underwater tasks more efficient, cost-effective, and generally safer. Raytheon Technology, specifically, is looking to improve their existing ballasting mechanism for their AUVs to use for military defense. For this …

The Development And Characterization Of Piezoelectric- Magnetostrictive Smart Self-Sensing Composites, George Relebohile Qhonosheane

Mechanical and Aerospace Engineering Dissertations - Archive

The composites industry is expanding due to the growing global demand for high-performance materials. How do you ensure the production of composites is as smooth and effective as possible while maintaining the high quality of the material? The key issues in composites include crack occurrence, sticking to molds in the production process, and durability differences during their operation. However, monitoring such cases can be challenging. The industry is in need of a smart solution to be able to obtain accurate data from the raw material. This work focuses on the development of smart composite materials. The word composite comes from …

Assessment Of Contaminant Flowpaths In Airside Economization And Analysis Of Thermal Performance At Tank And Server Level For Single-Phase Immersion Cooled Data Centers, Satyam Saini

Mechanical and Aerospace Engineering Dissertations - Archive

The last two decades of 2000 have seen an explosion of utilization and reliance on digital technologies and platforms. During this time, electronic devices have undergone intense miniaturization and a corresponding rise in power densities. In parallel to these developments, data center proliferation has been driven by the increasing utility of revolutionary technologies such as Machine Learning, Artificial Intelligence, e-commerce and, the Internet of Things. Data centers, thus, have become the core of the modern digital age. The primary bottleneck, however, due to extensive device miniaturization and data center proliferation has always been thermal management. Many of the aforementioned technologies …

Development Of An Electro-Pneumatic Servo Clutch And Industry-Level Controller, Timothy Stevens

Mechanical and Aerospace Engineering Theses - Archive

This thesis covers the simulation and development of an electro-pneumatic servo clutch used on an FSAE racecar. This project utilizes a sophisticated simulation and various techniques to increase performance such as utilizing pulse-width and pulse-frequency modulation and the use of a 36V supply with constant current limiting to drive the solenoids. The clutch is actuated using a pneumatic cylinder with the internal pressure modulated using commercially available CNG fuel injectors. This thesis also describes the development of the electronic controller designed using analog circuits, as well as the integration of digital circuits to control operations such as launch control and …

Computational Reliability Analysis Of Blind Micro-Via With 3d And Axisymmetric Multi-Layer Pcb, Jayendra Bazaru

Mechanical and Aerospace Engineering Theses - Archive

Micro-via are components that are used to form connections from one layer to another in most Multilayered Printed Circuit Boards (PCBs). The failure of Micro-via has always been a concern of the electronic industry. The failures are exaggerated during the reflow process due to the high thermal loading. Electronic components have become ubiquitous in our society. It is important to take some measures to reduce (or) eliminate the failures at interconnects in the Printed Circuit Board to obtain highly reliable Input/Output (I/O). This work is based on a hypothetical belief that the possible cause of failure is an insufficient or …

A Study On Effect Of Manufacturing Parameters On Morphology Of A356 Aluminum Foam, Nikhil Nanabhau Mahajan

All Theses

Metal foams have shown an excellent promise for usage as multifunctional material concerning research & development in the last 20 years. They provide remarkable mechanical as well as physical properties being lightweight. Open-cell metal foams have already been used in sound and noise absorption. Open-cell metal foams are outstanding for use in heat exchangers, filters, and many more applications, while closed-cell foams show excellent characteristics in impact energy absorptions. Closed-cell metal foams have higher energy absorption than their solid parent metal as they convert most of the impact energy into deformation energy. Metal foams have been used as prominent safeguard …

Autonomous Aerial Vehicles Distributed Control And Interactive Games, Yusuf Kartal

Mechanical and Aerospace Engineering Dissertations - Archive

As the number of quadrotors and other Unmanned Aerial Vehicles (UAVs) increases in industrial and urban areas, the development of reliable engineering methods to control their behavior as they interact with each other becomes of central interest in control research. With the increase in demand for UAVs to work together, several real-life challenges need to be addressed that include the implementation, test, and validation of the control algorithms in flight test experiments. On the one hand, the interests of UAVs may be in harmony to perform certain tasks such as transportation, surveillance and reconnaissance. On the other hand, the interests …

Enhancing Stability Of High-Nickel Cathodes For Lithium-Ion Batteries Through Additive Manufacturing Of Cathode Structure, Matthew Sullivan

Mechanical Engineering Undergraduate Honors Theses

Lithium-ion batteries (LIBs) are currently the best method to store electrical energy for use in portable electronics and electronic vehicles. New cathode materials for LIBs are consistently studied and researched, but few are as promising and attainable as nickel-rich transition metal oxides such as LiNi1-x-yMnxCoyO2 (NMC). NMC materials exist with many different mass ratios, but higher nickel content materials provide higher energy density. With this increase in capacity comes a sacrifice with cyclability, as high-nickel NMC variants are prone to structure collapse, transition metal dissolution, and cracks due to volume change. In this report, mechanical modification of the electrode by …

Modeling Energy Efficiency Of Solar Thermal Powered Batch Reverse Osmosis, Lahiri Chitturi

Discovery Undergraduate Interdisciplinary Research Internship

Batch reverse osmosis is the most energy efficient water desalination method and when powered by renewable energy, suggests promise for a cost-effective, low-carbon solution. One abundant energy source on Earth is solar energy which can be implemented using solar panels which have an established maximum efficiency of 25%, or solar thermal engines which can outperform solar photovoltaic systems by achieving higher efficiencies between 20% and 40% according to market research. Here, an approach to model and quantify the energy efficiency of a direct-drive solar thermal powered batch reverse osmosis system is presented to indicate the feasibility of pursuing this technology. …

Managing Humidity In Electronics Using Water Vapor-Selective Membranes, Songhao Wu, Andrew J. Fix, Allison Mou, David M. Warsinger, James Braun

Discovery Undergraduate Interdisciplinary Research Internship

Abstract: As outdoor electronics have become prevalent in every aspect of daily life, handling humidity in them is an emerging issue for reliable devices. As water vapor enters the electronics enclosure, there is a risk of condensation, which could prevent the electronics from functioning and further damage the device. Traditionally, the humidity removal for electronics is usually done by heating the air within the enclosure, which can be energy-intensive and less efficient. Vapor selective membrane systems are promising alternatives for air heating dehumidification as they do not require heating energy for water vapor removal. It allows water vapor transport through …

Control, Decision-Making, And Learning Approaches For Connected And Autonomous Driving Systems With Humans-In-The-Loop, Fangjian Li

All Dissertations

By virtue of vehicular connectivity and automation, the vehicle becomes increasingly intelligent and self-driving capable. However, no matter what automation level the vehicle can achieve, humans will still be in the loop despite their roles. First, considering the manual driving car as a disturbance to the connected and autonomous vehicles (CAVs), a novel string stability is proposed for mixed traffic platoons consisting of both autonomous and manual driving cars to guarantee acceptable motion fluctuation and platoon safety. Furthermore, humans are naturally considered as the rider in the passenger vehicle. A human-centered cooperative adaptive cruise control (CACC) is designed to improve …

Improved Digital Image Correlation Techniques At High Speed And High Temperature, Lindsey J. Rowley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In extreme environments, such as hot-fire rocket testing, gathering strain data can be challenging due to temperature constraints. Traditional methods for measuring material deformation such as strain gages, a small device attached to a test specimen, cannot withstand the extreme temperature and tend to burn off. When these situations occur non-contacting methods such as Digital Image Correlation (DIC) are preferable. DIC is an optical method of measuring strains across the material’s entire surface by using a camera to track the deformation of a speckle pattern applied to the surface of a deforming object. When used at temperatures above approximately 500°C, …

Seam Shifted Wake In The Magnus And Non-Magnus Directions, John W. Garrett

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

An experiment was done to look at the effect baseball seams can have on how a pitched baseball moves in flight. Both non-spinning and spinning baseballs were analyzed in this study. Data was taken and analyzed at 60, 90, and 110 MPH to determine the influence of velocity and altitude on the ability of seams to alter the trajectory of a pitched baseball. Additionally, a ball's spin causes movement in a certain direction that is dependent on the spin axis. A second focus of this study was on the effect of baseball seams changing the movement in the same direction …

Deep Learning Object-Based Detection Of Manufacturing Defects In X-Ray Inspection Imaging, Juan C. Parducci

Mechanical & Aerospace Engineering Theses & Dissertations

Current analysis of manufacturing defects in the production of rims and tires via x-ray inspection at an industry partner’s manufacturing plant requires that a quality control specialist visually inspect radiographic images for defects of varying sizes. For each sample, twelve radiographs are taken within 35 seconds. Some defects are very small in size and difficult to see (e.g., pinholes) whereas others are large and easily identifiable. Implementing this quality control practice across all products in its human-effort driven state is not feasible given the time constraint present for analysis.

This study aims to identify and develop an object detector capable …

Electromagnetic Modeling Of A Wind Tunnel Magnetic Suspension And Balance System, Desiree Driver

Mechanical & Aerospace Engineering Theses & Dissertations

Wind tunnels are used to study forces and moments acting on an aerodynamic body. While most results involve some interference from the mechanical supports used to hold the model, a Magnetic Suspension and Balance System (MSBS) is void of these interferences and presents an ideal test scenario. To further investigate the feasibility of dynamic stability testing at supersonic speeds using a MSBS, a preliminary design idea is currently being developed using an existing MSBS in a subsonic wind tunnel. This review focuses on the development of a mathematical model to more accurately portray the capabilities of the 6 inch Massachusetts …