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Acoustics, Dynamics, and Controls Commons

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Design Of Broadband Helmholtz Resonator Arrays Using The Radiation Impedance Method, Vidhya Rajendran, Andy Piacsek, Tomás Méndez Echenagucia 2022 University of Washington - Seattle Campus

Design Of Broadband Helmholtz Resonator Arrays Using The Radiation Impedance Method, Vidhya Rajendran, Andy Piacsek, Tomás Méndez Echenagucia

All Faculty Scholarship for the College of the Sciences

This paper describes the design process of a low-frequency sound absorptive panel composed of differently tuned Helmholtz resonators (HRs), considering size and fabrication constraints relevant for applications in the building sector. The paper focuses on cylindrical and spiral resonators with embedded necks that are thin and can achieve high absorption. the mutual interaction between the resonators was modeled based on the radiation impedance method and it plays a key component in enhancing the absorption performance of the array. The differential evolution search algorithm was used to design the resonators and modify their mutual interaction to derive the absorption performance of …


R/C Baja: Drivetrain, Connor T. Donovan 2022 Central Washington University

R/C Baja: Drivetrain, Connor T. Donovan

All Undergraduate Projects

The Central Washington University Mechanical Engineering Technology Department hosts an annual R/C Baja competition in which R/C cars fabricated by student teams are put through a series of courses and tests to determine which team's vehicle is best. The goal of this project was to create a functioning drivetrain that conveys power from the battery to the wheels and provides control of the vehicle. A list of requirements for the drivetrain was created to ensure that the vehicle will not only function, but that it will actually succeed in the competition. These requirements included that the vehicle must achieve a …


Kemar Hats Head Orientation Directivity, Samuel D. Bellows, Timothy W. Leishman 2022 Brigham Young University

Kemar Hats Head Orientation Directivity, Samuel D. Bellows, Timothy W. Leishman

Directivity

No abstract provided.


Generative Adversarial Networks For Extrapolation Of Corrosion In Automobile Images, Andre Von Zuben 2022 University of Central Florida

Generative Adversarial Networks For Extrapolation Of Corrosion In Automobile Images, Andre Von Zuben

Electronic Theses and Dissertations, 2020-

Deep learning has shown success in several applications involving pattern recognition, expert systems, and scientific discovery. However, existing methods struggle with industrial applications, which are often challenged by non-ideal datasets. In many cases, the datasets are small, poorly labeled, noisy, or have unbalanced class distribution or any combination of such problems. In this Master's research, we propose a generative adversarial network (GAN) strategy that is able to circumvent limitations imposed by tiny datasets. As a case study, we use the extrapolation of corrosion in automobiles and feed our deep learning framework with only a few dozen images instead of the …


Grinding And Super-Finishing Test Machine Project, Michael Simon 2022 The University of Akron

Grinding And Super-Finishing Test Machine Project, Michael Simon

Williams Honors College, Honors Research Projects

A research project in The University of Akron to study grinding and super-finishing of silicon nitride ceramic was initiated by Dr. Siamak Farhad and sponsored by the Timken Company, with the assistance of undergraduate students Michael Simon, Ryan Hosso and Mathew Rozmajzl. The study required analysis of forces and scratches generated during grinding processes of silicon nitride samples. A testing assembly was designed and constructed to record the forces generated during grinding and super-finishing of silicon nitride samples in a computer-numerical-control machine. Silicon nitride samples were subjected to desired grinding and super-finishing operations and all forces generated during the process …


Human Powered Vehicle Team Challenge, Sydney Nedlik, Spencer Brodie, Maria Griffin, William Schell, Ryan Serraglio 2022 The University of Akron

Human Powered Vehicle Team Challenge, Sydney Nedlik, Spencer Brodie, Maria Griffin, William Schell, Ryan Serraglio

Williams Honors College, Honors Research Projects

Design and build a Human Powered Vehicle in a team of five. Compete at the ASME HPVC competition in March of 2022. Re-establish the Human Powered Vehicle Team at the University of Akron.


Quickcut Waterjet Cutter, Kennedy Dunn, Jacob Storrow, Benjamin Laughrey 2022 The University of Akron

Quickcut Waterjet Cutter, Kennedy Dunn, Jacob Storrow, Benjamin Laughrey

Williams Honors College, Honors Research Projects

The QuickCut Waterjet Cutter was created in 2019 as a senior design project. This is the third iteration of the waterjet cutter. The goal of this project was to create an operable CNC waterjet cutter that is able to cut 1/16” tensile specimens consisting of nonferrous metal or plastic. This machine will be utilized in the Manufacturing Laboratory at the University of Akron to provide education to interested students on the waterjet cutting process, how it operates, and industrial application of the technology. Waterjet cutting is a subtractive manufacturing process which is recognized for its specialized applications such as cutting …


Multi-Platform Suppressor Design Project, Wyatt A. Openshaw, Alex B. Chiples 2022 The University of Akron

Multi-Platform Suppressor Design Project, Wyatt A. Openshaw, Alex B. Chiples

Williams Honors College, Honors Research Projects

The Multi-Platform suppressor is a design that is meant to bridge the gap in the suppressor market by being compatible and configurable with both rifle and pistol platform firearms. In the specific design and prototype referenced in this report, the Multi-Platform suppressor was designed to be used with 9mm pistol and 5.56x45mm rifle calibers with safety, effectiveness, and practicality in mind. To achieve this, the suppressor is configurable, utilizing a Nielsen device in the pistol configuration and a solid mount adapter that replaces the Nielson device piston and spring while in the rifle configuration. This allows the suppressor to retain …


Innovated Manual Wheelchair Propulsion, Jacob Eveleth, Abigail Steineman, James Murray, Garrett Best 2022 The University of Akron

Innovated Manual Wheelchair Propulsion, Jacob Eveleth, Abigail Steineman, James Murray, Garrett Best

Williams Honors College, Honors Research Projects

The goal of this project is to provide a manual wheelchair propulsion system that provides an easier way of moving the chair for the user. Our already-defined set of constraints and goals provides a clear end-goal for our group in accomplishing this task. We plan to have a 3D CAD model of the design by the end of the Spring 2022 semester. The first half of the Fall 2022 semester will be dedicated to developing a plan for prototyping, and the second half of the semester we plan to have the prototype created for use. So far, we have utilized …


Experimental Comparison Of Two Sampled-Data Adaptive Control Algorithms For Rejecting Sinusoidal Disturbances, William Grayson Woods 2022 University of Kentucky

Experimental Comparison Of Two Sampled-Data Adaptive Control Algorithms For Rejecting Sinusoidal Disturbances, William Grayson Woods

Theses and Dissertations--Mechanical Engineering

We review two adaptive control algorithms that address the problem of rejecting sinusoids with known frequencies that act on an unknown asymptotically stable linear time-invariant system. We present modifications to the algorithms that address the problems of sensor noise and actuator saturation. We demonstrate the effectiveness of the algorithms and compare the performance of the algorithms via numerical simulation and experimental testing.


Development Of An Improved Mathematical Representation Which Captures The Nonlinear Dynamic Behavior Of A Drill-String Assembly, Eleazar Marquez 2022 The University of Texas Rio Grande Valley

Development Of An Improved Mathematical Representation Which Captures The Nonlinear Dynamic Behavior Of A Drill-String Assembly, Eleazar Marquez

Mechanical Engineering Faculty Publications and Presentations

In this study, an improved mathematical representation of a drill-string assembly is developed to provide an alternative assessment on vibration irregularities proliferating downhole due to bit-rock interference. Lateral vibrations receive particular attention due to their high frequency content which alter the dynamic response of the drill-string, instigate casing damage, and impede optimal penetration rates. The response of the drill-string is captured by synthesizing compatible stationary bit excitations, via an auto-regressive digital filter, and implementing Monte Carlo simulation, while the power spectral density function is approximated to elucidate the dynamic characteristics during drilling. Formulating adequate physical parameters for the equation of …


Modeling Human Control Behavior In Command-Following Tasks, Sajad Koushkbaghi 2022 University of Kentucky

Modeling Human Control Behavior In Command-Following Tasks, Sajad Koushkbaghi

Theses and Dissertations--Mechanical Engineering

Humans interact with a variety of complex dynamic systems on a daily basis. However, they are often the lesser understood component of human-in-the-loop (HITL) systems. In this dissertation, we present the results of two HITL experiments to investigate the control strategies that humans use when performing command-following tasks. The first experiment is designed to investigate the control strategies that humans use to interact with nonlinear dynamic systems. Two groups of human subjects interact with a dynamic system and perform a command-following task. One group interacts with a linear time-invariant (LTI) dynamic system and the other group interacts with a Wiener …


The Effects Of Reference-Command Preview On The Strategies That Humans Use In Command-Following Tasks, Amelia J. S. Sheffler 2022 University of Kentucky

The Effects Of Reference-Command Preview On The Strategies That Humans Use In Command-Following Tasks, Amelia J. S. Sheffler

Theses and Dissertations--Mechanical Engineering

This thesis presents results from an experiment in which 22 human subjects each interact with a dynamic system 40 times over a one-week period. For each interaction, a subject performs a command-following task, where the reference command is the same for all 22 subjects but different on each trial. The subjects are divided into 2 groups of 11 subjects. One group performs the command-following task without reference-command preview. The other group is provided with 1-s preview of the reference command. The experimental results are used to examine the effects of reference-command preview. For the group with 1-s reference-command preview, the …


Precise Landing Of Vtol Uavs Using A Tether, Jeremy W. Rathjen 2022 West Virginia University

Precise Landing Of Vtol Uavs Using A Tether, Jeremy W. Rathjen

Graduate Theses, Dissertations, and Problem Reports

Unmanned Aerial Vehicles (UAVs), also known as drones, are often considered the solution to complex robotics problems. The significant freedom to explore an environment is a major reason why UAVs are a popular choice for automated solutions. UAVs, however, have a very limited flight time due to the low capacity and weight ratio of current batteries. One way to extend the vehicles' flight time is to use a tether to provide power from external batteries, generators on the ground, or another vehicle. Attaching a tether to a vehicle may constrain its navigation but it may also create some opportunities for …


Development And Validation Of A Force Measuring Device For A Laboratory Wave Tank, Jacob K. Colling 2022 Michigan Technological University

Development And Validation Of A Force Measuring Device For A Laboratory Wave Tank, Jacob K. Colling

Dissertations, Master's Theses and Master's Reports

The ability to predict the hydrodynamic force exerted on floating bodies plays a critical role in creating more effective control strategies for wave energy converters (WECs). Developing a test apparatus capable of directly measuring the forces exerted on a floating body subjected to a wavefield provides the means to validate theoretical prediction methods with experimental results and to develop data-based prediction methods for hydrodynamic forces. This report will discuss the development and validation of a device that measures the total vertical force exerted on a test artifact. The device requirements and design are discussed to examine the factors taken into …


On-Ice Detection, Classification, Localization And Tracking Of Anthropogenic Acoustic Sources With Machine Learning, Steven J. Whitaker 2022 Michigan Technological University

On-Ice Detection, Classification, Localization And Tracking Of Anthropogenic Acoustic Sources With Machine Learning, Steven J. Whitaker

Dissertations, Master's Theses and Master's Reports

Arctic acoustics have been of concern in recent years for the US navy. First-year ice is now the prevalent factor in ice coverage in the Arctic, which changes the previously understood acoustic properties. Due to the ice melting each year, anthropogenic sources in the Arctic region are more common: military exercises, shipping, and tourism. For the navy, it is of interest to detect, classify, localize, and track these sources to have situational awareness of these surroundings. Because the sources are on-water or on-ice, acoustic radiation propagates at a longer distance and so acoustics are the method by which the sources …


A Probabilistic Analysis In Vibration-Assisted Drilling To Measure Dynamic Behavior During Drilling And Understand Risk Factors, Eleazar Marquez, Samuel Garcia 2022 The University of Texas Rio Grande Valley

A Probabilistic Analysis In Vibration-Assisted Drilling To Measure Dynamic Behavior During Drilling And Understand Risk Factors, Eleazar Marquez, Samuel Garcia

Mechanical Engineering Faculty Publications and Presentations

In this paper, a mathematical representation is proposed to further understand the dynamic behavior and risk factors associated with vibration-assisted drilling (VAD) technology. The proposed Timoshenko beam model, which characterizes VAD technology, consists of two passive, counter-rotating coaxial rotors operating simultaneously, subjected to a stochastic excitation. In this regard, a finite element technique was incorporated to determine the physical parameters of the governing equation of motion, where the shear and rotary effects, as well as the gyroscopic couples generated perpendicular to the axis of rotation, were accounted for. Further, the relative velocity between the coaxial rotors was accounted in the …


Jet Engine Emissions And Vapor Contrail Reduction Through Increased Combustion Efficiency With The Aim To Mitigate Greenhouse Gases Emissions, Austin J. Brant 2022 Georgia Southern University

Jet Engine Emissions And Vapor Contrail Reduction Through Increased Combustion Efficiency With The Aim To Mitigate Greenhouse Gases Emissions, Austin J. Brant

Honors College Theses

As society continues to globalize and advance in complexity, the increased demand for business aviation has caused the global travel rate of airlines to increase with each year. With this continual increase in aviation travel, the Federal Aviation Administration (FAA) predicts that the fuel consumption rate is to increase by 1.6 percent as of the year 2025. While this increase in fuel consumption is a positive trait of a thriving aviation community, concerns also arise regarding increased greenhouse gas emissions and enlarged contributions to the greenhouse effect. The most prevalent greenhouse gases associated with jet engine emissions are water vapor, …


An Experimental Study Towards Underwater Propulsion System Using Structure Borne Traveling Waves, Shreyas suhas Gadekar 2022 Michigan Technological University

An Experimental Study Towards Underwater Propulsion System Using Structure Borne Traveling Waves, Shreyas Suhas Gadekar

Dissertations, Master's Theses and Master's Reports

The method of generating steady-state structure-borne traveling waves underwater in an infinite media creates abundant opportunities in the field of propulsive applications, and they are gaining attention from several researchers. This experimental study provides a framework for harnessing traveling waves in a 1D beam immersed under quiescent water using two force input methods and providing a motion to an object floating on the surface of the water.

In this study, underwater traveling waves are tailored using structural vibrations at five different frequencies in the range of 10Hz to 300Hz. The resulting fluid motion provides a propulsive thrust that moves a …


Estimation Of The Response, Power Spectra, And Whirling Patterns Generated From Mud Circulating Along The Annulus During Drilling Procedures: An Alternative Mathematical Representation Via Finite Element Modelling, Eleazar Marquez 2022 The University of Texas Rio Grande Valley

Estimation Of The Response, Power Spectra, And Whirling Patterns Generated From Mud Circulating Along The Annulus During Drilling Procedures: An Alternative Mathematical Representation Via Finite Element Modelling, Eleazar Marquez

Mechanical Engineering Faculty Publications and Presentations

In this study, an alternative mathematical representation of a drill-string is proposed to provide an alternative assessment on BHA dynamic alterations. Lateral vibrations remain the focal point of drill-string breakdowns given their high frequency characterization and ability to deviate perforation trajectories from the subsurface target. In this paper, the proposed model consists of an anisotropic rotor subjected to distinct RPMs, an axial force, and a bidirectional harmonic excitation with specified amplitude and assorted duration to simulate annulus motion generated from the mud fluid. In this regard, Euler-Bernoulli beam theory was adopted to establish a complete MDOF mathematical expression and thus …


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