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Wireless Sensor Integrated Tool For Characterization Of Machining Dynamics In Milling, Christopher Adam Suprock

Doctoral Dissertations

A first step towards practical sensing in the machining environment is the development and use of low cost, reliable sensors. Historically, the ability to record in-process data at an end mill tool tip has been limited by the sensor location. Often, these sensors are mounted on the material workpiece or the machine spindle at significant physical distance from the cutting process. Of specific interest are the problems of tool chatter which causes limitations to productivity and part quality. Although tool chatter is a substantial issue in machining, it remains an open research topic. In this research, a sensor integrated cutting …

Design Of A Low Power Switched-Capacitor Pipeline Analog-To-Digital Converter, Gang Chen

Doctoral Dissertations

An Analog to Digital Converter (ADC) is a circuit which converts an analog signal into digital signal. Real world is analog, and the data processed by the computer or by other signal processing systems is digital. Therefore, the need for ADCs is obvious.

In this thesis, several novel designs used to improve ADCs operation speed and reduce ADC power consumption are proposed. First, a high speed switched source follower (SSF) sample and hold amplifier without feedthrough penalty is implemented and simulated. The SSF sample and hold amplifier can achieve 6 Bit resolution with sampling rate at 10Gs/s.

Second, a novel …

Analytical And Numerical Prediction Of Localized Necking In Sheet Metal Forming Processes, Raed Zuhair Hasan

Doctoral Dissertations

The goal of this research is to investigate, develop and validate analytical and numerical tools that can accurately predict failure in sheet metal forming operations. The strain-based forming limit curve (FLC) is one of the tools to predict the maximum permissible strains of thin metallic sheets which are loaded in the plane of the sheet to different states of stress. It may be used to assess forming operations in the press shops as well as unintentional deformations, such as vehicle, aircraft, or train crashes. The accurate prediction of failure in sheet metal stamping can shorten product lead times, decrease tooling …

A Computational Fluid Dynamics Study Of Two-Phase Flows In The Presence Of Surfactants, Yuanyuan Cui

Doctoral Dissertations

Drop formation in co-flowing fluids and drops rising in a tube are important in applications such as microencapsulation and enhanced oil recovery. A hybrid volume-of-fluid method with a front-tracking scheme is developed to study two-phase flows in the presence of surfactants at finite Reynolds numbers. Both fluids can be Newtonian or shear-thinning, and surfactants are soluble in the adsorption-desorption limit. A drop in the co-flowing geometry typically breaks up at the primary neck. The drop breaks faster with smaller volumes as the outer flow rate increases or the drop viscosity decreases. When surfactants are present, they accumulate in the neck …

Development Of A Structural Parameter Estimation Program For Finite Element Model Updating, John A. Welch

Master's Theses and Capstones

The condition of America's infrastructure is highlighted by major collapses and overcrowded roadways remind us that our infrastructure is aging and in need of effective maintenance. The American Society of Civil Engineers report card for 2009 graded the nation's bridges as a C. In this period of renovation, rebuilding and limited funding, it is important to use the latest technologies to help make America's roadways safe and establish efficient management protocols. This research develops a program for the purpose of pairing structural health monitoring systems with the power of structural modeling, for the use of model updating and parameter estimation, …

On The Downstream Evolution Of The Mean Momentum Field In Turbulent Shear Wake Flows, Marc R. Bamberger

Master's Theses and Capstones

The evolution of shear wake flow formed from the interaction of two turbulent boundary layers was investigated. Primary interest was given to the post-separation region, very close to the trailing edge of the splitter plate. Two velocity ratios and two trailing edge geometries were explored. Data were acquired using four-element hotwire traverses for multiple downstream locations. With these data sets, a comparison to DNS data, the mean streamwise velocity and its wall normal gradients, Reynolds stress and its gradient, velocity intensities, the mean momentum balance were analyzed. A primary finding is that, post-separation, the inertial terms in the mean momentum …

Investigation Of Variables For Wireless Capacitive Strain Sensing On A Cnc Mill, Justin Patrick Bray

Master's Theses and Capstones

As demand in the manufacturing sector increases, so does the need for greater process throughput and reduced component variability. These two objectives can be achieved by a process known as 'smart machining'. Smart machining utilizes sensors inside the machining environment to relay information to the machine controller. Most sensor systems adversely affect the machine dynamics, by reducing the machining envelope or reducing the machine's stiffness, or require physical connections to conditioning electronics. In this research, variables regarding a resonantly coupled wireless capacitive strain sensor were investigated. A parallel plate capacitive sensor prototype system yielded a strain sensitivity five times greater …

Digital Image Correlation As A Tool For Bridge Load Rating And Long-Term Evaluation, Jason Thomas Peddle

Master's Theses and Capstones

Over 600,000 bridges are currently in service in the United States; one in three is considered either functionally obsolete or structurally deficient. The Federal Highway Administration defines structurally deficient bridge as one with a condition rating less than four on a scale from zero to nine. If a bridge is considered structurally deficient a load rating is determined. A load rating factor indicates the quantity of design live load that can be safely applied to the bridge. Rating factors are often the result of visual inspections and an analytical protocol that accounts for the effects that dead and live loads …

Design And Development Of A Debris Flow Tracking "Smart Rock", Matthew J. Harding

Master's Theses and Capstones

This thesis covers the design and development of a Smart Rock sensor package to be used in U.S. Geological Survey research of debris flow phenomena. This instrumented Rock, containing inertial sensors and pressure sensors, provides information about the movement of the flow as well as the pressures seen within the flow. The goal of the sensor package is to use this information to track the position of a particle in the flow with an accuracy of 1 m over the course of 10 s..

It is found that using an ad hoc filtering method provides the required level of accuracy. …

Accelerometer Calibration For Nasa's Magnetospheric Multiscale Mission Spacecraft, Benjamin M. Jenkins

Master's Theses and Capstones

This thesis presents several methods for the on-board and/or ground-based calibration of accelerometers for the spacecraft (s/c) of the NASA Magnetospheric Multi-Scale (MMS) Mission during mission operation. A lumped bias is estimated to correct for the total effect of the MMS accelerometer sensor bias, orthogonal misalignment and the shift in the s/c's center of mass.

Various estimation techniques are evaluated and compared, including both dynamically driven real-time filters/observers and post processing batch algorithms. Both methods are shown to accurately determine lumped bias, so long as the s/c inertia tensor is well known. If, however, there is any uncertainty in the …

A Two-Dimensional Hexagonal Network Model Of Alveolar Mechanics, Danielle Nangle

Master's Theses and Capstones

Pulmonary micromechanics (at the scale of alveoli) involves a delicate balance among tissue material properties, geometry, surface tension, pressure and stress distribution. To date, there is not a consensus among alveolar mechanics researchers about how these factors interact, in part because alveoli are so difficult to image and study in vivo. Here, we propose a basic mathematical model of a two-dimensional hexagonal network of mechanically coupled alveoli. We investigate equilibrium configurations of both dry and wet, internally pressurized elastic networks. Specifically, we compute pressure-area curves to quantify the differences among networks with different spring constants, internal pressures, network size and …

On The Ability Of Indentation To Capture The Anisotropic Elastic Properties Of The Pyrolytic Carbon, Nikolay Timoshchuk

Master's Theses and Capstones

We used micro- and nanoindentation, macroscopic strain gage methods and FE studies to correlate the indentation modulus and the macroscopic in- and out-of-plane Young's moduli of transversely isotropic pyrolytic carbon. The out-of-plane indentation modulus of bulk PyroC was comparable with predicted values and more than a factor of two higher than the out-of-plane Young's modulus. The in-plane indentation modulus was significantly lower than predicted values which we attribute to nanobuckling of graphite-like planes. Polarized light microscopy studies on carbon-carbon composite samples infiltrated at 10, 20, 30 kPa demonstrated that the increase in pressure leads to lower texture of the PyroC …

Climate Change Impact Reliability Of Large Electric Power Transformers In The Northeast United States, Krithikha Chinnaswamy

Master's Theses and Capstones

Global climate model simulations, when scaled to the Northeast U.S. region, indicate that New England will by 2100 experience many more days each summer of daily maximum temperatures in excess of 90°F. Given the strong correlation between summer heat waves and electric power demand, the stresses placed on the components of the electric grid by prolonged, elevated power demand is of obvious concern.

In this thesis a standard thermal model for large transformers is coupled with a temperature-dependent electric power demand model to predict the frequency of transformer thermal overload events during the months of June, July, and August through …

A Methodology For Evaluating The Implications Of Climate Change On The Design And Performance Of Flexible Pavements, William C. Meagher Iii.

Master's Theses and Capstones

A methodology is presented by which the implications of climate change on pavement deterioration can be assessed. This work focuses on the preparation and use of climate model datasets as inputs into the Mechanistic-Empirical Pavement Design Guide model to simulate pavement performance and deterioration over time. The methodology is illustrated using climate model temperature data from three North American Regional Climate Change Assessment Program scenarios at four sites across New England for alligator cracking and asphalt concrete rutting. The change in alligator cracking was shown to be negligible, while the difference in rutting was up to 31% between future and …

Real-Time Sampling-Based Motion Planning With Dynamic Obstacles, Kevin Rose

Master's Theses and Capstones

Autonomous robots are increasingly becoming incorporated in everyday human activities, and this trend does not show any signs of slowing down. One task that autonomous robots will need to reliably perform among humans and other dynamic objects is motion planning. That is, to reliably navigate a robot to a desired pose as quickly as possible while minimizing the probability of colliding with other objects. This involves not only planning around the predicted future trajectories of dynamic obstacles, but doing so in a real-time manner so that the robot can remain reactive to its surroundings. Current methods do not directly address …

Unconstrained Noninvasive Vital Signs Monitoring For Detection Of Obstructive Sleep Apnea With Automated Prevention, Jonathan Waters

Master's Theses and Capstones

The Bioengineering Laboratory at UNH has demonstrated the usefulness of medical device interoperability through previous work that involved connecting an advanced hospital bed with blood pressure monitors over an electrical communication bus known as Controller Area Network (CAN). The medical devices utilize the software communication protocol known as CANopen for communicating relevant patient data to one another. This thesis explores the opportunity to detect a person's heartbeat and respiration while lying in a hospital bed noninvasively and unconstrained for accurately identifying an episode of obstructive sleep apnea. The design and development of this device is a CANopen compatible therapeutic automatic …

The Effect Of Cutting Force Model Coefficient Variability On Process Planning In Milling, Firat Eren

Master's Theses and Capstones

This thesis describes the effect of force model uncertainty on process planning. Specifically, the statistical variations in model predicted machining forces while cutting aluminum, carbon steel, stainless steel and titanium are determined. An accurate estimate of the variability is essential for use in process planning to determine appropriate factors of safety when setting cutting conditions that are both safe and efficient.

Force model coefficient calibration is described and the variability in the coefficients is determined through a least squares regression of a large number of experimental cuts. It is shown that the variability increases with changes in the calibration cutting …

Supporting International Students To Meet Assessment Expectations, W. Gornisiewicz, O. Bass

Research outputs 2011

This paper offers practical suggestions for teaching strategies that will assist international students. A case study is presented involving the delivery of an introductory engineering unit at the Perth Institute of Business and Technology. The approach detailed allowed the academic staff to identify areas of concern in students’ learning early in the semester. Detecting and addressing these issues led to a signifi cant improvement in preparing these students to meet the exam requirements.

Engineering Mathematics And Virtual Learning Environments: A Case Study Of Student Perceptions, Annette Louise Taylor

School of Engineering, Computing and Mathematics Theses

The study involved BTec National (level 3) engineering students studying at a large Further Education College in the South West region. The disciplines of Electrical/Electronic, Mechanical, Operations and Maintenance, Manufacturing, Telecommunications and Fabrication where all included in the study. Several students were sent by their employers on day release programmes and apprenticeships, and these formed the majority of the part time students. There were also other employed students who attended full time for terms 1 and 3 as part of a block release programme. The remaining students were full time, and mainly 16-18 years old. The study focused upon the …

Computational Investigation Of Particle Settling Effects On Inhaled Submicron Bioaerosol Deposition In The Human Lung, Mohammed Ali, Essam A. Ibrahim

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 1-5

Motion Tracking Through Machine Vision, Poonam Savsani, Vimal Savsani

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 14-21

Asme Early Career Technical Journal (Complete Issue), Asme Ectc Coordinating Committee

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

Evaluation Of Pulse Jet Mixing Using A Scalar Quantity And Shear Stress, Ibraheem R. Muhammad, John P. Kizito

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 45-52

A Study Of Tissue Strains Induced In Airways Due To Mechanical Ventilation, Trenicka Rolle, Ramana Pidaparti

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 136-141

Ocean Wave Energy Generator, Francis S. Fernandez, Bader Ale, Alfonso Parra, Sabri Tosunoglu

Early Career Technical Journal (ECTJ)

Proceedings of the ASME Early Career Technical Conference, November 4-5, 2011. Woodruff School of Mechanical Engineering, Georgia Institute of Technology, Atlanta, Georgia

pp. 142-148

An Approach To Improve The Failure Rate Model Of A Solid State Laser By Utalizing The Physics Of Failure Methodology, Omar L. Thompson

Electronic Theses and Dissertations

The ability to predict the failure rate of any military laser is very critical. In-field laser usage does not support the troubleshooting and repairing of a complex electro optical system. The only published laser failure rate model was last updated by the Department of Defense in 1975. Consequently, the failure rate predicted is inaccurate due to model deficiencies. This dissertation has developed a laser failure rate model for diode pumped lasers with improved failure rate prediction accuracy. The model has surpassed the capabilities of the Department of Defense model by the inclusion of key performance attributes that are currently not …

A Model Study Of Adlayer Pattern Formation Of A Linear Molecule On Square And Triangular Lattices, Gennadiy N. Berezutskiy

Master's Theses and Capstones

We have determined patterning and geometric properties of rigid-diatomic-molecular rotors, fixed on (square and triangular) the lattice site modeled by the Morse potential. Zero-K adlayer patterns were enhanced through the implementation of unconstrained multivariable function using derivative-free method (also known as simplex algorithm). Results have been obtained over wide geometry range for adlayer patterns composed of periodically repeated primary cell.

A primary focus of this work was the calculation of adlayer free energies and geometry at the ground state. Those were obtained from conformational search of the primary (2x2) cell to locate geometric configuration, which minimizes the total energy. The …

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Engineering Graduates: Preparation And Progression: Institutes Of Technology Honours Bachelor Degree Engineering Graduate Study, June, 2011, James Shivnan, Austin Hanley, Mike Murphy

Reports

The national strategy for higher level education underlines the importance of innovation and enterprise; and well qualified engineers are central to furthering that strategy. This honours bachelor degree engineering graduate study represents an intense dialogue between engineering faculties across the Institutes of Technology to gain insight into the quality of our engineering education. The study provides a fresh insight into how NFQ Level 81honours bachelor degree engineering graduates from the Institutes are perceived by employers, how well the graduates themselves feel they are prepared to perform as engineers, and how both employers and graduates judge the strengths and weaknesses of …

2010 Fall Engr333 Project Final Report, 2010 Fall Engr333

ENGR 333

Calvin College dorms have a chronic issue with wasting energy. The dorms have little insulation, high infiltration rates, and are heated by low efficiency boilers. These existing characteristics combine for a larger required heating load and increased energy usage. The excess heat, due to poor temperature control, is often vented out through the windows whenever students deem necessary. This project will attempt to reduce wasted energy and efficiently distribute heat as needed.

The Thermal Systems Design class of 2010 was challenged with retrofitting the Bolt-Heyns-Timmer (BHT) dorm to decrease energy consumption and improve efficiency. The class was presented with the …