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Full-Text Articles in Mechanical Engineering

Mechatronic Education At The Faculty Of Technical Sciences Novi Sad, Gordana Ostojić, Vukica Jovanović, Drazan Kozak, Zeljko Ivandić, Stevan Stankovski Jan 2015

Mechatronic Education At The Faculty Of Technical Sciences Novi Sad, Gordana Ostojić, Vukica Jovanović, Drazan Kozak, Zeljko Ivandić, Stevan Stankovski

Engineering Technology Faculty Publications

The emerging engineering field of mechatronics has caught the attention of many engineering professionals, academics and government officials in recent years, nationally and globally. The main reason for this is that many modern products are no longer purely electrical and electronic or mechanical. Moreover, they are integrated multidisciplinary products which are made from subsystems which require engineering knowledge of different disciplines. Hence, increasing number of universities is offering courses, certificates and programs at undergraduate and graduate levels in the area of mechatronics. This paper presents an educational program in mechatronics at the Faculty of Technical Sciences, University of Novi Sad, …


Performance Of Self-Excited Energy Harvesters With Tip Bodies Of Non-Circular Cross Section Shapes, Joan Manuel Gomez Jan 2015

Performance Of Self-Excited Energy Harvesters With Tip Bodies Of Non-Circular Cross Section Shapes, Joan Manuel Gomez

Dissertations and Theses

An experimental study on the performance of self-excited energy harvesters with non-circular tip body shapes has been performed. The two tip body shapes analyzed correspond to a half cylinder and a square cross section. Experiments are carried out in the wind tunnel to record the voltage output of the harvesters at different free stream velocities. The presence of the aeroelastic galloping instability was detected by the behavior of the transversal tip displacement of the harvester as well as the coupling of the motion and shedding frequency from the bluff body. The effect of tip mass, free stream turbulence, tip body …


Computational Modeling To Assess Surgical Procedures For The Treatment Of Adult Acquired Flatfoot Deformity, Brian A. Smith Jan 2015

Computational Modeling To Assess Surgical Procedures For The Treatment Of Adult Acquired Flatfoot Deformity, Brian A. Smith

Theses and Dissertations

Several surgically corrective procedures are considered to treat Adult Acquired Flatfoot Deformity (AAFD) patients, relieve pain, and restore function. Procedure selection is based on best practices and surgeon preference. Recent research created patient specific models of Adult Acquired Flatfoot Deformity (AAFD) to explore their predictive capabilities and examine effectiveness of the surgical procedure used to treat the deformity. The models’ behavior was governed solely by patient bodyweight, soft tissue constraints, and joint contact without the assumption of idealized joints. The current work expanded those models to determine if an alternate procedure would be more effective for the individual. These procedures …


A Review Of Locomotion Systems For Capsule Endoscopy, Lejie Liu,, Shahrzad Towfighian, Amine Hila Jan 2015

A Review Of Locomotion Systems For Capsule Endoscopy, Lejie Liu,, Shahrzad Towfighian, Amine Hila

Mechanical Engineering Faculty Scholarship

Wireless capsule endoscopy for gastrointestinal (GI) tract is a modern technology that has the potential to replace conventional endoscopy techniques. Capsule endoscopy is a pill-shaped device embedded with a camera, a coin battery, and a data transfer. Without a locomotion system, this capsule endoscopy can only passively travel inside the GI tract via natural peristalsis, thus causing several disadvantages such as inability to control and stop, and risk of capsule retention. Therefore, a locomotion system needs to be added to optimize the current capsule endoscopy. This review summarizes the state-of-the-art locomotion methods along with the desired locomotion features such as …


A Cylindrical Triboelectric Energy Harvester For Capsule Endoscopes, Lejie Liu, Shahrzad Towfighian, Zhanpeng Jin Jan 2015

A Cylindrical Triboelectric Energy Harvester For Capsule Endoscopes, Lejie Liu, Shahrzad Towfighian, Zhanpeng Jin

Mechanical Engineering Faculty Scholarship

Capsule endoscopy is a new technology that has the potential to replace conventional endoscopy in the near future due to its non-invasive nature. A major limitation for their functionality is the limited battery life. We have investigated a triboelectric energyharvester inside a capsule endoscope that can generate power from natural contractions of gastrointestinal (GI) tract. The periodic contacts and separations of two triboelectric materials inside the capsule endoscope create an alternating current that can be used to charge the capsule endoscope battery, which is used for imaging the GI tract. This study presents an analytical closed form solution for the …


Buckling Instability Of Crown Sealing, J. O. Marston, Mohammad M. Mansoor, Tadd T. Truscott, S. T. Thoroddsen Jan 2015

Buckling Instability Of Crown Sealing, J. O. Marston, Mohammad M. Mansoor, Tadd T. Truscott, S. T. Thoroddsen

Mechanical and Aerospace Engineering Faculty Publications

Despite the scholarly fascination with water entry of spheres for well over a century,1 we present a new observation, namely, the crown-buckling instability. This instability is characterized by striations appearing near the top of the crown walls just prior to the surface seal, as shown in Fig. 1(a). The crown wall collapses inward due to the pressure differential across the wall created by the moving air in the wake of the sphere and surface tension within the crown. Since the rate of collapse is faster than that at which fluid drains out from the neck region, fluid collects into …


High Regression Rate Hybrid Rocket Fuel Grains With Helical Port Structures, Stephen A. Whitmore, Sean D. Walker, Daniel P. Merkley, Mansour Sobbi Jan 2015

High Regression Rate Hybrid Rocket Fuel Grains With Helical Port Structures, Stephen A. Whitmore, Sean D. Walker, Daniel P. Merkley, Mansour Sobbi

Mechanical and Aerospace Engineering Faculty Publications

Results froma development campaign, where modern additive manufacturing methods are used to fabricate hybrid rocket fuel grains with embedded helical ports, are presented. The fuel grains were constructed from acrlyonitrile butadiene styrene using commercially available three-dimensional printer feedstockmaterial.Gaseous oxygen is used as the oxidizer for this test campaign.When compared to cylindrical fuel ports, significant increases in fuel regression rates were observed, and these increases in regression rate diminished with time as the helical fuel port burns to become progressivelymore cylindrical. Comparisons to the helical pipe flow skin friction correlation developed by Mishra and Gupta indicate that increased skin friction only …


Matryoshka Cavity, Randy Craig Hurd, T. Fanning, Zhao Pan, C. Maybey, Kyle G. Bodily, Kip Schafer Hacking, Nathan B. Spiers, Tadd T. Truscott Jan 2015

Matryoshka Cavity, Randy Craig Hurd, T. Fanning, Zhao Pan, C. Maybey, Kyle G. Bodily, Kip Schafer Hacking, Nathan B. Spiers, Tadd T. Truscott

Mechanical and Aerospace Engineering Faculty Publications

When a water droplet impacts a free surface with sufficient velocity, the momentum transfer results in the formation of a hemispherical cavity expanding radially from the point of impact.1 This cavity continues to expand until the kinetic energy is completely converted to potential energy (Fig. 1(a)).2 Pumphrey and Elmore equated the potential energy of this subsurface cavity with the kinetic energy of the impacting droplet, concluding that the magnitude of the cavity radius is proportional to impact velocity and droplet diameter.3


Experimental Validation Data For Cfd Of Mixed Convection On A Vertical Flat Plate, Blake W. Lance, Jeff R. Harris, Barton L. Smith Jan 2015

Experimental Validation Data For Cfd Of Mixed Convection On A Vertical Flat Plate, Blake W. Lance, Jeff R. Harris, Barton L. Smith

Mechanical and Aerospace Engineering Faculty Publications

Model validation for Computational Fluid Dynamics(CFD), where experimental data and model outputs are com-pared, is a key tool for assessing model uncertainty. In this work, mixed convection is studied experimentally for the purpose of providing validation data for CFD models with a high level of completeness. Experiments are performed in a facility built specifically for validation with a vertical, flat,heated wall. Data were acquired for both buoyancy-aided and buoyancy-opposed flows. Measured boundary conditions include as-built geometry, inflow mean and fluctuating velocity profiles, and inflow and wall temperatures. Additionally, room air temperature, pressure, and relative humidity are measured to provide fluid …


The Study Of Frequency-Scan Photothermal Reflectance Technique For Thermal Diffusivity Measurement, Zilong Hua, Heng Ban, David H. Hurley Jan 2015

The Study Of Frequency-Scan Photothermal Reflectance Technique For Thermal Diffusivity Measurement, Zilong Hua, Heng Ban, David H. Hurley

Mechanical and Aerospace Engineering Faculty Publications

A frequency scan photothermal reflectance technique to measure thermal diffusivity of bulk samples is studied in this manuscript. Similar to general photothermal reflectance methods, an intensity-modulated heating laser and a constant intensity probe laser are used to determine the surface temperature response under sinusoidal heating. The approach involves fixing the distance between the heating and probe laser spots, recording the phase lag of reflected probe laser intensity with respect to the heating laser frequency modulation, and extracting thermal diffusivity using the phase lag–(frequency)1/2 relation. The experimental validation is performed on three samples (SiO2, CaF2, and …


Spacecraft Attitude Control Using Magnetic Actuators, Karthik Mysore Srinivasa Jan 2015

Spacecraft Attitude Control Using Magnetic Actuators, Karthik Mysore Srinivasa

Dissertations, Master's Theses and Master's Reports - Open

This report presents a study on the problem of spacecraft attitude control using magnetic actuators. Several existing approaches are reviewed and one control strategy is implemented and simulated. A time-varying feedback control law achieving inertial pointing for magnetically actuated spacecraft is implemented. The report explains the modeling of the spacecraft rigid body dynamics, kinematics and attitude control in detail.

Besides the fact that control laws have been established for stabilization around local equilibrium, this report presents the results of a control law that yields a generic, global solution for attitude stabilization of a magnetically actuated spacecraft. The report also involves …


Optical Access Engine Setup And Validation, Jiongxun (Justin) Zhang Jan 2015

Optical Access Engine Setup And Validation, Jiongxun (Justin) Zhang

Dissertations, Master's Theses and Master's Reports - Open

The optical access engine integrated with the diagnostic and optical measurement techniques is a great platform for engine research because it provides clear visual access to the combustion chamber inside the engines. An optical access engine customized based on a 4-cylinder spark ignited direct injection (SIDI) production engine is located in the Advanced Power Systems Laboratories (APS LABS) at Michigan Technological University. This optical access engine inside the test cell has been set up for different engine research.

In this report, two SAE papers in engine research utilizing the optical access engine are reviewed to gain basic understanding of the …


Development And Validation Of A Radtherm Model To Predict Exhaust System Behavior For A Hybrid Xm1124 Hmmwv, Souman Haldar Jan 2015

Development And Validation Of A Radtherm Model To Predict Exhaust System Behavior For A Hybrid Xm1124 Hmmwv, Souman Haldar

Dissertations, Master's Theses and Master's Reports - Open

Accurately predicting component temperatures, and the influence various subsystems have on each other prior to hardware development and testing is an important aspect of the vehicle development process. In this report, a 1-D thermal model is used for predicting the behavior of the exhaust system and underbody area of prototype Hybrid Electric HMMWV XM1124. This prototype vehicle is designed to be capable of exporting up to 15 kW of electrical power to a micro-grid or similar operation. However, in this project instead of exporting power to a micro-grid, 6.5 kW of power was used to charge the batteries and increase …


Modelling And Control Of Combustion Phasing Of An Rcci Engine, Kaveh Khodadadi Sadabadi Jan 2015

Modelling And Control Of Combustion Phasing Of An Rcci Engine, Kaveh Khodadadi Sadabadi

Dissertations, Master's Theses and Master's Reports - Open

Reactivity controlled compression ignition (RCCI) is a novel combustion strategy introduced to achieve near-zero NOx and soot emissions while maintaining diesel-like efficiencies. Meanwhile, precise control of combustion phasing is a key in realization of high fuel conversion efficiency as well as meeting stringent emission standards. Model-based control of RCCI combustion phasing is a great tool for real-time control during transient operation of the engine, which requires a computationally efficient combustion model that encompasses factors such as, injection timings, fuel blend composition and reactivity. In this thesis, physics-based models are developed to predict the combustion metrics of an RCCI engine. A …


Structural Analysis Of Integration Of A Non-Cylindrical Cng Fuel Tank, Prathamesh Prashant Deshpande Jan 2015

Structural Analysis Of Integration Of A Non-Cylindrical Cng Fuel Tank, Prathamesh Prashant Deshpande

Dissertations, Master's Theses and Master's Reports - Open

The purpose of this study is to computationally model and analyze the vehicle frame which is mounted with a non-conventional, non-cylindrical compressed natural gas (CNG) fuel tank. Integration of this tank in the vehicle underbody will resolve the issue of reduced storage space which is observed in a conventional CNG powered vehicle. This research will ultimately result in making CNG a good alternative to gasoline and reducing the increasing dependency on a single fuel. This tank will be developed in two phases: phase I design of the tank will be a standard rectangular outer box shape with Schwarz P-surface inner …


Mechanical Characterization Of Bamboo And Glass Fiber Biocomposite Laminates, Matthew Siniawski Jan 2015

Mechanical Characterization Of Bamboo And Glass Fiber Biocomposite Laminates, Matthew Siniawski

Mechanical Engineering Faculty Works

Single-ply biocomposite laminates were fabricated with two different woven fabrics and a bio-based resin using a wet layup technique at room temperature. A highly elastic, stockinette weave bamboo fiber fabric and a thicker, inelastic plain weave bamboo fabric were both investigated. The elastic fabric was pre-strained at 25% intervals, ranging from 0-100% of its original length. Samples made with E-Glass and S-Glass, two common glass fiber reinforcements, were also fabricated using the bioresin as benchmarks. The ultimate strength and modulus of elasticity characteristics of the composites were determined using the ASTM D3039/ D3039M-08 standard test method for determining the tensile …


Thermographic Investigation Of Laser Metal Deposition, Sreekar Karnati Jan 2015

Thermographic Investigation Of Laser Metal Deposition, Sreekar Karnati

Masters Theses

"Laser metal deposition as an additive manufacturing technique has been proven to possess the capability for fabricating complex, intricate geometries and excellent material properties through material deposition. Accurate manufacture of such geometric features would require precise control over the material deposition process. The need of the hour are process monitoring and analyses mechanisms that are crucial in ascertaining the occurrence of the intended actions during deposition while also serving as effective learning tools. The current work involved developing and incorporating an Infra-Red (IR) camera as a process monitoring tool for laser metal deposition. Using the IR camera the thermal dynamics …


Laser Surface And Sub-Surface Repair During Metal Additive Manufacturing, Prudvi Teja Ravi Jan 2015

Laser Surface And Sub-Surface Repair During Metal Additive Manufacturing, Prudvi Teja Ravi

Masters Theses

"This study examines the use of laser surface treatment to repair surface and subsurface defects. Numerical analysis was performed on laser surface melting using Gaussian heat distribution equations to analyze the depth of the melt pool created by the phenomena. Concurrently, a process map was developed with a planned set of experiments by varying the ranges of laser power and travel speed to determine the dimensions of the melt pool across the gamut. The data generated from both the process studies and the numerical analysis was then used to determine the ideal operating ranges of the process parameters to repair …


Generation And Validation Of Optimal Topologies For Solid Freeform Fabrication, Purnajyoti Bhaumik Jan 2015

Generation And Validation Of Optimal Topologies For Solid Freeform Fabrication, Purnajyoti Bhaumik

Masters Theses

"The study of fabricating topologically optimized parts is presented hereafter. The mapping of topology optimization results for Standard Tessellation Language (STL) writing would enable the solid freeform fabrication of lightweight mechanisms. Aerospace leaders such as NASA, Boeing, Airbus, European Aeronautic Defense And Space Company (EADS), and GE Aero invest in topology optimization research for the production of lightweight materials. Certain concepts such as microstructural homogenization, discretization, and mapping are reviewed and presented in the context of topology optimization. Future biomedical applications of solid freeform fabrication such as organ printing stand to save millions of lives through the robust development of …


Freeze-Form Extrusion Fabrication Of Boron Carbide, Aaron Scott Thornton Jan 2015

Freeze-Form Extrusion Fabrication Of Boron Carbide, Aaron Scott Thornton

Masters Theses

"Boron carbide is a safe, alternative to beryllium as a material for aerospace structures since it is also light-weight and exhibits high strength. This paper discusses a study of the Freeze-form Extrusion Fabrication (FEF) process to fabricate parts from boron carbide. Process parameters and hardware were modified to fabricate boron carbide specimens free of printed defects. Four-point bending tests were performed to measure the flexural strength of fabricated specimens. Observations of the presence of voids caused by ice crystals in fabricated parts led to further development and characterization of the boron carbide paste used with the FEF process. Additives were …


Freeform Extrusion Fabrication Of Titanium Fiber Reinforced 13-93 Bioactive Glass Scaffolds, Albin Thomas Jan 2015

Freeform Extrusion Fabrication Of Titanium Fiber Reinforced 13-93 Bioactive Glass Scaffolds, Albin Thomas

Masters Theses

"Although implants made with bioactive glass have shown promising results for bone repair, their application in repairing load-bearing long bones is limited due to their poor mechanical properties as compared to human bones. This thesis study is on freeform extrusion fabrication of silicate based 13-93 bioactive glass scaffolds reinforced with titanium fibers. A composite paste was prepared with 13-93 bioactive glass filled with titanium fibers (~16 µm in diameter and aspect ratio of ~250) having 0.1 to 0.4 vol. % of the bioactive glass scaffold. This paste was then filled into a syringe manually, and then extruded through a nozzle …


Estimation Of Tip-Sample Force In Tapping Mode Atomic Force Microscopy Using Neural-Network And Repetitive Control Approaches, Alireza Toghraee Jan 2015

Estimation Of Tip-Sample Force In Tapping Mode Atomic Force Microscopy Using Neural-Network And Repetitive Control Approaches, Alireza Toghraee

Masters Theses

"Atomic Force Microscopy is one of the most powerful tools for imaging, measuring and manipulating materials at nanometer scale. Among different modes of AFM, tapping mode, in which the oscillating tip touches the sample periodically, is most common mode. During the tip approach and retract, the tip interacts with sample and experiences different force regimes. This tip-sample interaction force contains information about the sample topology, material properties and tip geometry. However, quantitative measurement of the time-varying tip-sample interaction forcing function is challenging in the tapping mode because of the combined dynamic complexities of the cantilever and nonlinear complexity of the …


Nanoindentation Of A Zinc Metal Soap Mixture For Use In A Laser Printer, George A. Nimick Jan 2015

Nanoindentation Of A Zinc Metal Soap Mixture For Use In A Laser Printer, George A. Nimick

Theses and Dissertations--Chemical and Materials Engineering

At the start of this project, the possible choices of metal soaps had already been narrowed to include some of the zinc soaps used in this project. These zinc soaps are mixtures of zinc stearate and zinc palmitate of varying ratios purchased from a supplier. Zinc soap was chosen as result of its common use in various industries as a lubricant and mold release, which implied potential benefits in an electrophotographic printing system. These potential benefits include, but are not limited to, a more efficient transfer from a photoconductive drum and protection of the drum from mechanical and chemical degradation. …


Engineered Surface Properties Of Porous Tungsten From Cryogenic Machining, Julius M. Schoop Jan 2015

Engineered Surface Properties Of Porous Tungsten From Cryogenic Machining, Julius M. Schoop

Theses and Dissertations--Chemical and Materials Engineering

Porous tungsten is used to manufacture dispenser cathodes due to it refractory properties. Surface porosity is critical to functional performance of dispenser cathodes because it allows for an impregnated ceramic compound to migrate to the emitting surface, lowering its work function. Likewise, surface roughness is important because it is necessary to ensure uniform wetting of the molten impregnate during high temperature service. Current industry practice to achieve surface roughness and surface porosity requirements involves the use of a plastic infiltrant during machining. After machining, the infiltrant is baked and the cathode pellet is impregnated. In this context, cryogenic machining is …


Machining Strategies Exploring Reduction In Energy Consumption, Abdullah Al Mamun Jan 2015

Machining Strategies Exploring Reduction In Energy Consumption, Abdullah Al Mamun

All Graduate Theses, Dissertations, and Other Capstone Projects

The main aim of this thesis is to explore machining strategies, analyzing energy consumption using Design of Experiments (DOE) at the material removal rate (MRR), compare to cutting geometrical trajectories according to CNC parameters such as spindle RPM, feed rate, depth of cut per pass and total depth of cut. Spindle RPM, depth of cut per pass, and feed rate are selected as the main three factors and each factor has two levels: low-level (-) and high-level (+). These experiments have been performed at an end-milling machine by using a concept of a constant volume of material removal processes in …


A Stroke Of Shear Genius: The Development Of The Blade Bandit, Abdulrahman Hamid Jan 2015

A Stroke Of Shear Genius: The Development Of The Blade Bandit, Abdulrahman Hamid

Honors Theses

This thesis will document and analyze the experience of two members of the Shear Genius team, Mr. Abdulrahman Hamid and Mr. Colin Wattigney, as they worked to complete the CME Senior Capstone Project. This team, under the leadership of CEO Ethan Veazey, developed the Blade Bandit, a lawn mower blade sharpening system conceptualized by Mr. Jacob Moorhead. Ms. Kristen Gaddis, Mr. Nick Rocco, and Ms. Allie Winters were also members of Shear Genius. The team members had educational backgrounds in the realms of engineering, business and accountancy. The combination of these disciplines allowed for the simulation of a real business …


Novel Classification Of Slow Movement Objects In Urban Traffic Environments Using Wideband Pulse Doppler Radar, Berta Rodriguez Hervas Jan 2015

Novel Classification Of Slow Movement Objects In Urban Traffic Environments Using Wideband Pulse Doppler Radar, Berta Rodriguez Hervas

Open Access Theses & Dissertations

Every year thousands of people are involved in traffic accidents, some of which are fatal. An important percentage of these fatalities are caused by human error, which could be prevented by increasing the awareness of drivers and the autonomy of vehicles. Since driver assistance systems have the potential to positively impact tens of millions of people, the purpose of this research is to study the micro-Doppler characteristics of vulnerable urban traffic components, i.e. pedestrians and bicyclists, based on information obtained from radar backscatter, and to develop a classification technique that allows automatic target recognition with a vehicle integrated system. For …


A Heterogeneous Multiscale Method For Poroelasticity, Paul M. Delgado Jan 2015

A Heterogeneous Multiscale Method For Poroelasticity, Paul M. Delgado

Open Access Theses & Dissertations

In this Thesis, we develop and analyze a heterogeneous multiscale model for coupled fluid flow and solid deformation in porous media based on operator splitting and finite volume method. The splitting method results in two elliptic multiscale PDE's in the form of a reaction diffusion equation and a linear elasticity equation. We extend our previous multiscale method from 1D to higher dimensions and develop new approaches for the inclusion of mixed boundary conditions and source terms. We derive an error estimate for our multiscale method and analyze the stability of our splitting method. We also test the effectiveness of our …


Reaction Of Liquid Aluminium- Samarium Alloys With B4c At Ultra High Temperatures, Sanjay Shantha-Kumar Jan 2015

Reaction Of Liquid Aluminium- Samarium Alloys With B4c At Ultra High Temperatures, Sanjay Shantha-Kumar

Open Access Theses & Dissertations

Reactive studies between a packed bed of B4C and Al-Sm-Me (Me = Ti, Zr, Hf) alloy melts were carried out under a pseudo-isopiestic thermodynamic system. A graphite enclosure isolated the system under a temperature gradient with one end reaching temperatures greater than 1800 K and the opposite end of the graphite enclosure contains liquid Al with temperatures approximating 950 K. The liquid Al establishes an oxygen potential to control oxidation of very reactive elements (i.e., Al, Sm and Ti). The Al-Sm-Me alloy infuses into a packed bed of B4C reacting exothermically to form borides and carbides depending on the thermodynamic …


Defeating Anisotropy In Material Extrusion 3d Printing Via Materials Development, Ángel Ramón Torrado Pérez Jan 2015

Defeating Anisotropy In Material Extrusion 3d Printing Via Materials Development, Ángel Ramón Torrado Pérez

Open Access Theses & Dissertations

Additive Manufacturing technologies has been in continuous development for more than 35 years. Specifically, the later denominated Material Extrusion Additive Manufacturing (MEAM), was first developed by S. Scott Crump around 1988 and trademarked later as Fused Deposition Modeling (FDM). Although all of these technologies have been around for a while, it was not until recently that they have been more accessible to everyone. Today, the market of 3D printers covers all ranges of price, from very specialized, heavy and expensive machines, to desktop printers of only a few cubic inches in volume. Until recently, FDM technology had remained somewhat stagnant …