Mechanical Engineering Commons^™

Zips Electric Racing Suspension Design, Christopher Thompson, Madison Hughes, Erikah Jackson, Anna Signorino

Williams Honors College, Honors Research Projects

As a member of the 2020 Zips Electric Racing Design Team, I will design the suspension subsystem with three other members. Specifically concentrating on the steering and suspension mounting points, we will optimize and improve some components from the previous year's design. Modeling of components will be done in Solidworks and suspension vehicle behavior will be modeled in MATLAB and Optimum Kinematics.

Quickcut Cnc Waterjet Cutter, Kelly V. Robbins

Williams Honors College, Honors Research Projects

This design project was dedicated to improving the existing design and making functional the QuickCut CNC Waterjet Cutter. The scope of work consisted of making the machine mobile and more structurally stable as well as programming the CNC controls. The project was started in the 2018/19 school year by a former mechanical engineering student. The subsystems consist of the frame, power, motor, water pump and associated plumbing, nozzle, abrasive feed system, x/y gantry, Arduino control system and the cutting bed. Unfortunately, due to the COVID-19 pandemic, the full scope was not able to be completed in its entirety.

Tabletop Mechanical Tester, Jamie Dombroski, Brian English, Richard Leffler, Andrew Shirk

Williams Honors College, Honors Research Projects

The need for hands-on and face-to-face experiences in the engineering classroom is very great. The equations, principles, and concepts can all be learned, but without the visual and tactile application, these don’t always sink in or become concrete. A small-scale tensile test machine was designed, sourced, manufactured, and tested for the purpose of being applied in classroom settings to provide this experience to engineering students. Extensive research was performed concerning tensile machines on the market, the essential elements of which are the load cell, grips, crosshead, extensometer, motor, and frame. The raw materials for the frame were purchased and drawings …

Autonomous Guided Vehicle Frame For Outdoor Use, Thomas Mcgrath

Williams Honors College, Honors Research Projects

The overall goal for my project is to design a durable Autonomous Guided Vehicle (AGV) frame intended for carrying a heavy load over outdoor terrain. I will not be designing a complete vehicle, only the basic structure that can be used to build a complete AGV on. There will be complete 3D models of the design and its individual parts. I also would like to provide limited Finite Element Analysis of the design using ANSYS software to determine weaknesses and methods for improvement. The design I create is meant to be used as a framework for complete outdoor AGV designs. …

Rinse Tank Salinity Automation, George Pahoundis

Williams Honors College, Honors Research Projects

Manufacturing processes are often consisted of many different processes and sub-processes. Each of these carries its own level of importance and impact to the overall picture. In this particular sub-process, salt is rinsed from a product via a rinse tank: a tank whose salinity may not exceed a certain level and whose temperature must not fall below a certain level. This setting is a prime opportunity to implement an automated control system to allow these parameters to be met with upmost efficiency. With potential savings in excess of $20,000 per year and an estimated payback period of 8 weeks, the …

Enhancement Of The Syncardia Total Artificial Heart For Pediatric Use, Margaret Clark, Madison Marks

Williams Honors College, Honors Research Projects

Pediatric patients with disorders and diseases of the heart have limited options with regards to implantable devices. Many of these implants are ventricular assist devices, which is not always suitable for a patient. Total artificial hearts (TAHs) have supported many adult patients until transplantation, and we believe that they could do the same for pediatric patients. SynCardia has the only Food and Drug Administration (FDA) approved TAH devices. Since SynCardia is the only company with FDA approved TAHs, we decided to modify the design of the SynCardia TAH for use in pediatric patients without compromising the function of the current …

Quantification And Modeling Of Bladder Biomechanics Mechanisms Linking Spontaneous Rhythmic Contractions And Dynamic Elasticity To Detrusor Overactivity, Zachary E. Cullingsworth

Theses and Dissertations

Overactive bladder (OAB) is a chronic condition affecting approximately 20% of adults in the United States. Detrusor overactivity (DO) is the presence of non-voiding contractions in the detrusor (bladder) muscle during filling and is present in some individuals with OAB. DO is currently identified visually during a urodynamics (UD) study involving pressure catheters and filling and voiding of the bladder to evaluate function. UD provides limited subtyping of DO, and an incomplete understanding of mechanisms contributing to OAB.

Aim 1 of this study was to develop objective tools to quantify, subgroup and better understand …

Defect Modeling And Vibration-Based Bending Fatigue Of Additively Manufactured Inconel 718, Wesley Earl Eldt

Browse all Theses and Dissertations

Additive manufacturing (AM) is convenient for building components with complex features. However, the long-term integrity of these components is uncertain, since AM parts have defects such as pores and rough surfaces. In this work, an analytical model was developed to determine the impact of defects, and a novel bending fatigue test was used to determine the fatigue life of channeled specimens. The analytical model, based off the theory of critical distances, investigates coupled pores and predicts their potential for fatigue failure. This resulted in a maximum allowable pore size and spacing recommendation for coupled defects. Additionally, specimens with through channels …

Adaptive Multi-Fidelity Modeling For Efficient Design Exploration Under Uncertainty, Atticus J. Beachy

Browse all Theses and Dissertations

This thesis work introduces a novel multi-fidelity modeling framework, which is designed to address the practical challenges encountered in Aerospace vehicle design when 1) multiple low-fidelity models exist, 2) each low-fidelity model may only be correlated with the high-fidelity model in part of the design domain, and 3) models may contain noise or uncertainty. The proposed approach approximates a high-fidelity model by consolidating multiple low-fidelity models using the localized Galerkin formulation. Also, two adaptive sampling methods are developed to efficiently construct an accurate model. The first acquisition formulation, expected effectiveness, searches for the global optimum and is useful for modeling …

Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey

Browse all Theses and Dissertations

The presence of defects within laser powder bed fusion (LPBF) parts can lead to reduced mechanical properties and life of components. Because of this, the ability to detect these defects within the parts is critical before the part is subject to its intended loading. Normally the parts are subjected to a quality analysis once they are completed however, this process is typically expensive and time consuming. A solution for these problems is to sense the creation of defects and pores in the parts in-situ, while the part is being fabricated. One proposed method of in-situ monitoring is visible spectroscopy to …

Turbine Passage Vortex Response To Upstream Periodic Disturbances, Mitchell Lee Scott

Browse all Theses and Dissertations

Flow through the turbine section of gas turbine engines is inherently unsteady due to a variety of factors, such as the relative motion of rotors and stators. In low pressure turbines, periodic wake passing has been shown to impact boundary layer separation, blade surface pressure distribution, and loss generation. The effect of periodic disturbances on the endwall flow is less understood. Endwall flow in a low-pressure turbine occurs in the boundary layer region of the flow through the blade passage where the blade attaches to the hub in the turbine. The response of an endwall vortical structure, the passage vortex, …

In Vivo Data Capture Using Hssr For Calibration Of Computational Models, Thor Erik Andreassen

Electronic Theses and Dissertations

Computational modeling is a vital tool for understanding and evaluating healthy and unhealthy function of the musculoskeletal aspects of the human body. However, the accuracy of the musculoskeletal models depends significantly on the accuracy of the input data used to calibrate various behavioral parameters of the model. To date, most computational models have been built using generic in vitro data, mostly because of a lack of accurate and meaningful datasets from in vivo testing. The next major step in computational modeling is to create subject-specific computational models using calibration data taken from in vivo testing. The overall goal was to …

Identification Of Heat Release Shapes And Combustion Control Of An Ltc Engine, Radhika Sitaraman

Dissertations, Master's Theses and Master's Reports

Low Temperature Combustion (LTC) regimes have gained attention in internal combustion engines since they deliver low nitrogen oxides (NOx) and soot emissions with higher thermal efficiency and better combustion efficiency, compared to conventional combustion regimes. However, the operating region of these high-efficiency combustion regimes is limited as it is prone to knocking and high in-cylinder pressure rise rate outside the engine safe zone. By allowing multi-regime operation, high-efficiency region of the engine is extended. To control these complex engines, understanding and identification of heat release rate shapes is essential. Experimental data collected from a 2 liter 4 cylinder LTC engine …

Efficient Enhancement Of Micro-Nucleation Rates In Flow-Boiling - By Concurrent Micro-Structuring Of The Boiling-Surface And Its Judicious Energization By Piezoelectric-Transducer Induced Acoustic Vibrations., Atharva Rahane

Dissertations, Master's Theses and Master's Reports

The report describes the science and technology backgrounds and uses for the technology breakthrough reported for enhanced flow-boiling based cooling of high-power density electronics (chips, memory etc.). A controlled but explosive growth in micro-scale nucleation rates during flow-boiling of HFE-7100 (electronics and environment friendly liquid from 3M, Inc) is enabled by the uses of inexpensive meshed-copper for micro-structuring of the boiling surface and a pair of Piezoelectric-transducers for active imposition of suitable acoustic vibrations. The pair of piezo transducers mounted just outside the mini-channel impose “in plane” acoustic vibrations of controllable amplitudes and frequencies, and they are used to induce …

Heterogeneous Uncertainty Quantification For Reliability-Based Design Optimization, Mingyang Li

Dissertations, Master's Theses and Master's Reports

Uncertainty is inherent to real-world engineering systems, and reliability analysis aims at quantitatively measuring the probability that engineering systems successfully perform the intended functionalities under various sources of uncertainties. In this dissertation, heterogeneous uncertainties including input variation, data uncertainty, simulation model uncertainty, and time-dependent uncertainty have been taken into account in reliability analysis and reliability-based design optimization (RBDO). The input variation inherently exists in practical engineering system and can be characterized by statistical modeling methods. Data uncertainty occurs when surrogate models are constructed to replace the simulations or experiments based on a set of training data, while simulation model uncertainty …

Using Transfer Path Analysis And Frequency Based Substructuring To Develop A Robust Vibration Laboratory Dynamic Test Fixture Design Process, Cora Taylor

Dissertations, Master's Theses and Master's Reports

The objective of this research is to determine a robust method for designing shock and vibration laboratory test fixtures that accurately reproduce the field environment for the component of interest. The methods presented in this research examine the boundary conditions presented unto the component of interest through transfer path analysis with the intent of reproducing the next-structure attachment impedance with a laboratory test fixture of one and two attachments. The first method includes only using the next-structure relative motion and stiffness to design a test fixture, while the second method uses an optimization algorithm to develop a lumped parameter model …

Experimental Evaluation Of An Rwd Vehicle With Parameter Extraction For Analytical Modeling And Evaluation, Jon Furlich

Dissertations, Master's Theses and Master's Reports

This study was conducted to perform experimental vibration testing on a light duty rear wheel drive vehicle. The vehicle is known to have excessive longitudinal acceleration response perceived after step changes in the driver torque command. The excessive response includes shuffle and clunk transients. Experimental testing was performed to understand the coupling between driver torque commands and peak shuffle oscillations. Data was also targeted to understand the coupling between driveline torsional oscillations and longitudinal vehicle vibrations. This data was also used to establish vehicle parameters for use in an analytical CAE model of the driveline and coupling. Driver applied tip-in …

Measurement Of Current Distribution In The Land Channel Direction Of A Proton Exchange Membrane Fuel Cell, Chinmay Kulkarni

Dissertations, Master's Theses and Master's Reports

A fully functional proton exchange membrane fuel cell with single land channel geometry on the cathode and segmented anode current collector with 9 mm² active area with a 350μm spatial resolution was utilized to measure the local current distribution in the land channel direction. A distinguished printed circuit board approach was used for the data acquisition to adapt to any flow field design.

Performance of this segmented cell was examined at dry, wet and moderate humidity settings to study the water transport phenomenon in the PEMFC. In the dry condition at 60 ͦ C with 0% relative humidity, the …

High-Performance Zero Liquid Discharge (Zld) Treatment Of High-Salinity Brines Using A Multiple-Effect Absorption Distillation Concept, Sunil Pinnu

Dissertations, Master's Theses and Master's Reports

State-of-the-art zero liquid discharge (ZLD) technologies are currently bound with either intensive use of high-grade electrical energy such as mechanical vacuum vapor compressors utilized in brine crystallizers or high capital cost with environmental concerns such as evaporation ponds. The present study aims to address these issues by an innovative desiccant-based ZLD system in which a multiple-effect distillation (MED) unit is uniquely embedded at the heart of an absorption-desorption system. Here, the MED and absorption systems are inherently coupled enabling both heat and mass transfer processes between a high-salinity water and a desiccant solution. The proposed technology employs an absorption-based thermally-driven …

Sensor Fusion And Non-Linear Mpc Controller Development Studies For Intelligent Autonomous Vehicular Systems, Ahammad Basha Dudekula

Dissertations, Master's Theses and Master's Reports

The demand for safety and fuel efficiency on ground vehicles and advancement in embedded systems created the opportunity to develop Autonomous controller. The present thesis work is three fold and it encompasses all elements that are required to prototype the autonomous intelligent system including simulation, state handling and real time implementation. The Autonomous vehicle operation is mainly dependent upon accurate state estimation and thus a major concern of implementing the autonomous navigation is obtaining robust and accurate data from sensors. This is especially true, in case of Inertial Measurement Unit (IMU) sensor data. The IMU consists of a 3-axis gyro, …

Optimal Mission Planning Of Autonomous Mobile Agents For Applications In Microgrids, Sensor Networks, And Military Reconnaissance, Casey D. Majhor

Dissertations, Master's Theses and Master's Reports

As technology advances, the use of collaborative autonomous mobile systems for various applications will become evermore prevalent. One interesting application of these multi-agent systems is for autonomous mobile microgrids. These systems will play an increasingly important role in applications such as military special operations for mobile ad-hoc power infrastructures and for intelligence, surveillance, and reconnaissance missions. In performing these operations with these autonomous energy assets, there is a crucial need to optimize their functionality according to their specific application and mission. Challenges arise in determining mission characteristics such as how each resource should operate, when, where, and for how long. …

Bibliometric Analysis Of Bearing Fault Detection Using Artificial Intelligence, Pooja Kamat, Rekha Sugandhi Dr.

Library Philosophy and Practice (e-journal)

The new industrial revolution called Industry 4.0 is proliferating at its peak. The time is no longer away when the human race is going to witness a huge paradigm shift. Intelligent machines empowered by Artificial Intelligence (AI)will take over the presence of human workers in the industrial manufacturing sector with the target of achieving 100% automation. With the emergence of cut-throat price competition in the product market, it has become equally important to manufacture goods at minimal costs and with the highest quality. Predicting the decrease in machinery efficiency at an earlier stage to accomplish this objective helps to reduce …

Nanothermomechanical And And Or Logic Gates, Ahmed Hamed, Sidy Ndao

Department of Mechanical and Materials Engineering: Faculty Publications

Today’s electronics cannot perform in harsh environments (e.g., elevated temperatures and ionizing radiation environments) found in many engineering applications. Based on the coupling between near-field thermal radiation and MEMS thermal actuation, we presented the design and modeling of NanoThermoMechanical AND, OR, and NOT logic gates as an alternative, and showed their ability to be combined into a full thermal adder to perform complex operations. in this work, we introduce the fabrication and characterization of the first ever documented Thermal AND and OR logic gates. Theresults show thermal logic operations can be achieved successfully through demonstrated and easy-to- manufacture nanothermoMechanical logic …

Electrospun Thymosin Beta-4 Loaded Plga/Pla Nanofiber/ Microfiber Hybrid Yarns For Tendon Tissue Engineering Application, Shaohua Wu, Rong Zhou, Fang Zhou, Philipp N. Streubel, Shaojuan Chen, Bin Duan

Department of Mechanical and Materials Engineering: Faculty Publications

Microfiber yarns (MY) have been widely employed to construct tendon tissue grafts. However, suboptimal ultrastructure and inappropriate environments for cell interactions limit their clinical application. Herein, we designed a modified electrospinning device to coat poly(lactic-co-glycolic acid) PLGA nanofibers onto polylactic acid (PLA) MY to generate PLGA/PLA hybrid yarns (HY), which had a well-aligned nanofibrous structure, resembling the ultrastructure of native tendon tissues and showed enhanced failure load compared to PLA MY. PLGA/PLA HY significantly improved the growth, proliferation, and tendon-specific gene expressions of human adipose derived mesenchymal stem cells (HADMSC) compared to PLA MY. Moreover, thymosin beta-4 (Tβ4) loaded PLGA/PLA …

Additive Manufacturing Of Magnesium Alloys, Rakeshkumar Karunakaran, Sam Ortgies, Ali Tamayol, Florin Bobaru, Michael P. Sealy

Department of Mechanical and Materials Engineering: Faculty Publications

Magnesium alloys are a promising new class of degradable biomaterials that have a similar stiffness to bone, which minimizes the harmful effects of stress shielding. Use of biodegradable magnesium implants eliminates the need for a second surgery for repair or removal. There is a growing interest to capitalize on additive manufacturing's unique design capabilities to advance the frontiers of medicine. However, magnesium alloys are difficult to 3D print due to the high chemical reactivity that poses a combustion risk. Furthermore, the low vaporization temperature of magnesium and common biocompatible alloying elements further increases the difficulty to print fully dense structures …

Passivation Of Defects In Perovskite Materials For Improved Solar Cell Efficiency And Stability, Jinsong Huang, Xiaopeng Zheng

Department of Mechanical and Materials Engineering: Faculty Publications

Semiconductor devices, and methods of forming the same, include a cathode layer, an anode layer, and an active layer disposed between the cathode layer and the anode layer, wherein the active layer includes a perovskite layer. A passivation layer is disposed directly on a surface of the active layer between the cathode layer and the active layer, the passivation layer including a layer of material that passivates both cationic and anionic defects in the surface of the active layer.

3d Printing Of Multilayered Scaffolds For Rotator Cuff Tendon Regeneration, Xiping Jiang, Shaohua Wu, Mitchell Kuss, Yunfan Kong, Wen Shi, Philipp N. Streubel, Tieshi Li, Bin Duan

Department of Mechanical and Materials Engineering: Faculty Publications

Repairing massive rotator cuff tendon defects remains a challenge due to the high retear rate after surgical intervention. 3D printing has emerged as a promising technique that enables the fabrication of engineered tissues with heterogeneous structures and mechanical properties, as well as controllable microenvironments for tendon regeneration. In this study, we developed a new strategy for rotator cuff tendon repair by combining a 3D printed scaffold of polylactic-co-glycolic acid (PLGA) with cell-laden collagen-fibrin hydrogels. We designed and fabricated two types of scaffolds: one featuring a separate layer-by-layer structure and another with a tri-layered structure as a whole. Uniaxial tensile tests …

Imparities Of Shear Avalanches Dynamic Evolution In A Metallic Glass, Yin Du, Qing Zhou, Qian Jia, Yidi Shi, Haifeng Wang, Jian Wang

Department of Mechanical and Materials Engineering: Faculty Publications

The imparities of shear avalanches dynamic evolution under nanoindentation originating from the soft regions and the stiff matrix were explored in a metallic glass by statistical and dynamic analysis. Upon the continuous indentation process, the dynamic state of the stiff matrix exhibits a transition from a chaotic behavior to a self-organized critical (SOC) behavior, whereas the soft regions are domi-nated by the SOC behavior throughout the indentation process. The mechanism was clarified by the evolution of the cut-off size of shear avalanches. These findings might advance our fundamental understanding of inhomogeneous deformation on microscale.

IMPACT STATEMENT The shear avalanches dynamic …

Foundry Sand Source Reduction Options: Life Cycle Assessment Evaluation, Samuel Ghormley, Robert Williams, Bruce Dvorak

Department of Mechanical and Materials Engineering: Faculty Publications

Foundries represent a significant part of the world’s economy and are a large consumer of energy and producer of solid waste. Sand-handling processes can use 5–10% of a foundry’s total energy. The goal of this research was to explore source reduction and waste minimization at a foundry, using both economic and Life Cycle Assessment (LCA) techniques to compare three secondary sand-reclamation options. LCA software modeled all sand processes at a mid-sized ferrous foundry in the USA. The LCA showed all secondary reclamation technologies, while more energy intensive at the foundry, lowered life cycle environmental impacts, including GHG emissions, ecotoxicity, and …

An Overview Of Additive Manufacturing Technologies—A Review To Technical Synthesis In Numerical Study Of Selective Laser Melting, Abbas Razavykia, Eugenio Brusa, Cristiana Delprete, Reza Yavari

Department of Mechanical and Materials Engineering: Faculty Publications

Additive Manufacturing (AM) processes enable their deployment in broad applications from aerospace to art, design, and architecture. Part quality and performance are the main concerns during AM processes execution that the achievement of adequate characteristics can be guaranteed, considering a wide range of influencing factors, such as process parameters, material, environment, measurement, and operators training. Investigating the effects of not only the influential AM processes variables but also their interactions and coupled impacts are essential to process optimization which requires huge efforts to be made. Therefore, numerical simulation can be an effective tool that facilities the evaluation of the AM …