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The Effect Of Noise-Reducing Acoustic Panels On The Noise Levels And Overall Safety Of Infant Sleep Machines, Pranav Poola 2021 Spring Valley High School

The Effect Of Noise-Reducing Acoustic Panels On The Noise Levels And Overall Safety Of Infant Sleep Machines, Pranav Poola

Journal of the South Carolina Academy of Science

Infant sleep machines (ISMs) are devices used to help infants fall asleep faster and stay asleep for longer amounts of time, yet they can often be too loud for infantile ears, which could potentially be dangerous. This research aimed to minimize the risks of infant sleep machines without reducing the effectiveness of the infant sleep machines themselves through the use of acoustic panels. Based on previous studies, it was hypothesized that the acoustic panels would reduce the noise levels of the ISM to less than recommended limits of 50 dB-A. A specific corner of a designated room was prepared with …


Nonlinear Model Development And Validation For Ball And Plate Control System, Zachary Richter 2021 California Polytechnic State University, San Luis Obispo

Nonlinear Model Development And Validation For Ball And Plate Control System, Zachary Richter

Master's Theses

Ball and plate balancing control systems are commonly studied due to the complex dynamics associated with the instability of the system in open-loop. For simplicity, mathematical models describing the ball and plate dynamics are often linearized and the effects of complex motion are assumed to be negligible. These assumptions are rarely backed with evidence or explanations validating the simplified form of the dynamical equations of motion. This thesis focuses on developing a nonlinear model that more accurately defines the dynamics of the system, in order to quantify the error of linear and nonlinear models when compared to a Simscape physical …


Simultaneous Estimation And Modeling Of Nonlinear, Non-Gaussian State-Space Systems, Josiah Steckenrider, Tomonari Furukawa 2021 United States Military Academy

Simultaneous Estimation And Modeling Of Nonlinear, Non-Gaussian State-Space Systems, Josiah Steckenrider, Tomonari Furukawa

West Point Research Papers

This paper presents a framework for simultaneous estimation and modeling of nonlinear, non-Gaussian state-space systems. In the proposed approach, uncertainty in motion model parameters is incorporated to avoid overconfidence in state prediction and better account for modeling inaccuracies. The additional original contribution of a model correction stage improves nonlinear model parameter estimates in order to enhance the accuracy of state estimation. The presented nonlinear/non-Gaussian Simultaneous Estimation And Modeling (SEAM) approach was compared with contemporary estimation techniques using a Monte-Carlo simulation study. This study showed that the proposed method successfully reduces estimation error relative to existing approaches even when substantial model …


Development And Applications Of Adjoint-Based Aerodynamic And Aeroacoustic Multidisciplinary Optimization For Rotorcraft, Ramiz Omur Icke 2021 Old Dominion University

Development And Applications Of Adjoint-Based Aerodynamic And Aeroacoustic Multidisciplinary Optimization For Rotorcraft, Ramiz Omur Icke

Mechanical & Aerospace Engineering Theses & Dissertations

Urban Air Mobility (UAM) is one of the most popular proposed solutions for alleviating traffic problems in populated areas. In this context, the proposed types of vehicles mainly consist of rotors and propellers powered by electric motors. However, those rotary-wing components can contribute excessively to noise generation. Therefore, a significant noise concern emerges due to urban air vehicles in or around residential areas. Reducing noise emitted by air vehicles is critically important to improve public acceptance of such vehicles for operations in densely populated areas.

Two main objectives of the present dissertation are: (1) to expand the multidisciplinary optimization to …


Inverted Fluorescence Microscope, Matthew B. Pfeiffer, Spencer George Hann, Thomas James Eggenberger, Trevor Lee Blythe 2021 California Polytechnic State University, San Luis Obispo

Inverted Fluorescence Microscope, Matthew B. Pfeiffer, Spencer George Hann, Thomas James Eggenberger, Trevor Lee Blythe

Mechanical Engineering

Team F13 is composed of Trevor Blythe, Spencer Hann, Matthew Pfeiffer, and Thomas Eggenberger. We are all majoring in mechanical engineering and in our final year of study here at Cal Poly San Luis Obispo. This project is a continuation of a 2019-2020 senior project. The previous team designed and built a functioning inverted fluorescence microscope (IFM) from scratch. This device was created as a lab tool for undergraduate students to be able to perform experiments on microfluidic devices constructed in Cal Poly’s Microfabrication Laboratory. Although substantially functional, several design constraints had not yet been met. Our team has improved …


Vibration Isolation For Scanning Tunneling Microscope, Seth Ewing, Ryan McMullen, Jason Behrens, Stephen DeHerrera 2021 California Polytechnic State University, San Luis Obispo

Vibration Isolation For Scanning Tunneling Microscope, Seth Ewing, Ryan Mcmullen, Jason Behrens, Stephen Deherrera

Mechanical Engineering

Scanning Tunneling Microscopy (STM) works by scanning a fine metal wire over a conductive sample in order to image samples on the atomic level. The microscope uses a feedback loop with a PID controller to maintain a constant tunneling current between the sample and the tip. In order to obtain clear imaging at the atomic level, the microscope and the sample need to be isolated from external vibrations in a vacuum chamber. The scope for this project is to build and test a single-stage vibration isolation system that effectively attenuates the amplitude of external vibrations acting on the microscope. This …


Cnc Feed Drive Control, Ryan J. Funchess, Caleb P. O'Gorman, Nick J. DeSimone, Juan M. Majano, Samuel K. Wong 2021 California Polytechnic State University, San Luis Obispo

Cnc Feed Drive Control, Ryan J. Funchess, Caleb P. O'Gorman, Nick J. Desimone, Juan M. Majano, Samuel K. Wong

Mechanical Engineering

This document serves as the Final Design Report (FDR) for a senior project developed by our team: four senior Mechanical Engineering students and one computer engineering student at California Polytechnic State University, San Luis Obispo (Cal Poly). While the project was completed for, and sponsored by, Professor Simon Xing of Cal Poly, the remainder of the university’s controls professors will be indirectly benefited from this project. Our goal was to design and implement a functional CNC Feed Drive to be used for educational demonstrations and data collection. This document discusses our early product research and benchmark goals, which established constraints …


Private Sound Environments In Public Space: Use Of Headphones In Public Parks And Public Transit, Chathurthi S. De Silva 2021 New Jersey Institute of Technology

Private Sound Environments In Public Space: Use Of Headphones In Public Parks And Public Transit, Chathurthi S. De Silva

Dissertations

The use of headphones is now so commonplace that it is almost second nature for many people to use them. Not only do these people use headphones all the time, but they use them nearly everywhere, including in urban public spaces. In using headphones, people create their own “private sound environments” in public space. This phenomenon merits attention from researchers since the creation of private sound environments may well alter people’s experiences of public space.

This study answers five research questions about the use of headphones in parks and on transit: why people use them, when they begin using headphones …


Classroom Room Acoustics And Effect On Speech With And Without Face Coverings In Direct And Reverberant Sound Fields, Danny Hernandez-Borjas 2021 Kennesaw State University

Classroom Room Acoustics And Effect On Speech With And Without Face Coverings In Direct And Reverberant Sound Fields, Danny Hernandez-Borjas

Symposium of Student Scholars

Prior to the COVID-19 pandemic, life consisted of seeing people in dense public areas such as malls, parks, and schools. But the life these people once knew has changed with face coverings becoming more prevalent in society along with social distancing which caused these public places to limit their capacity. However, a certain faction of society-this being students, have been affected immensely due to this transition of life at school which includes mandatory face coverings in the classroom and social distancing. This research focuses on the effects on speech with and without face coverings in a classroom setting in certain …


Real-Time Monitoring Of Fdm 3d Printer For Fault Detection Using Machine Learning: A Bibliometric Study, Vaibhav Kisan Kadam, Satish Kumar, Arunkumar Bongale 2021 Symbiosis International University

Real-Time Monitoring Of Fdm 3d Printer For Fault Detection Using Machine Learning: A Bibliometric Study, Vaibhav Kisan Kadam, Satish Kumar, Arunkumar Bongale

Library Philosophy and Practice (e-journal)

Additive Manufacturing has wide application range including healthcare, Fashion, Manufacturing, Prototypes, Tooling etc. AM techniques are subjected to various defects that may be printing defects or anomalies in machine. There is gap between current AM techniques and smart manufacturing since current AM lacks in build sensors necessary for process monitoring and fault detection. Both of these issues can be solved by incorporating real-time monitoring into AM. So the study is carried out to identify recent work done in AM to improve current system. For this bibliometric study Scopus database is used, study is kept limited to year 2010-2021 and English …


Magnetic Gradient-Based Magnetic Tweezer System For 3d And Swarm Control Of Microswimmer, Xiao Zhang 2021 Southern Methodist University

Magnetic Gradient-Based Magnetic Tweezer System For 3d And Swarm Control Of Microswimmer, Xiao Zhang

Mechanical Engineering Research Theses and Dissertations

Microscale manipulation has very promising potential in medical applications such as drug delivery, minimal and invasion surgery. Contactless control is preferable as remote manipulation is necessary for in vivo applications. Among different control methods, magnetic power source is more suitable and robust for the applications mentioned above. Presented here is a magnetic tweezer system, which manipulates microscale magnetic particles using magnetic forces created by magnetic field gradient. The proposed system has three advantages: First, force applied by the magnetic tweezer system does not contact with the target object and can be generated in different directions. Second, the magnetic tweezer system …


Actuation And Control Methods For Individual And Swarm Multiscale Mechanical Systems, Pouria Razzaghi 2021 Southern Methodist University

Actuation And Control Methods For Individual And Swarm Multiscale Mechanical Systems, Pouria Razzaghi

Mechanical Engineering Research Theses and Dissertations

Robotic mechanisms can be driven by different internally and externally applied inertial and magnetic actuations. These actuations are utilized to regulate the dynamics of robots and move them in different locomotion modes. The first part of this dissertation is about using an external magnetic actuation to move a simple-in-design, small-scale robot for biomedical applications. The robots can be steered in different locomotion modes such as pivot walking and tumbling. The control design of this system consists of a swarm algorithm under a global control input, and a vision-based closed-loop controller to navigate in 2D environments.

Secondly, I propose a new …


Active Blade Pitch And Hull-Based Structural Control Of Floating Offshore Wind Turbines, Eben Lenfest 2021 University of Maine

Active Blade Pitch And Hull-Based Structural Control Of Floating Offshore Wind Turbines, Eben Lenfest

Electronic Theses and Dissertations

Floating offshore wind turbines (FOWTs) have the potential to bring renewable energy to waters too deep for traditional offshore wind turbines while still being able to harness strong coastal winds in areas near population centers. However, these floating wind turbines come at a higher capital cost relative to fixed foundations and are more susceptible to vibrations induced by waves. Advances in control technologies offer the potential to reduce fatigue loads due to these vibrations, extending the life of the platform and thereby spreading the capital costs of the turbine over a longer period of time. One such advance is in …


Mathematical Modeling Of A Two Wheeled Robotic Base, Kathryn Remell 2021 University of Arkansas, Fayetteville

Mathematical Modeling Of A Two Wheeled Robotic Base, Kathryn Remell

Mechanical Engineering Undergraduate Honors Theses

This thesis presents the concept of using a two wheeled robot on the moon and briefly explores the requirements for successful long term operation in a lunar environment. The mathematical model for the motion of a robot with two fixed wheels on a differential drive with in a global reference frame. The robot is assumed to be balancing a platform so the mathematical model to balance the platform with wheel motors is also developed and briefly evaluated.


Computational Study On Suppression Of Airfoil Flow Separation Using High-Frequency Translational Surface Actuation, Bibek Gupta 2021 University of Mississippi

Computational Study On Suppression Of Airfoil Flow Separation Using High-Frequency Translational Surface Actuation, Bibek Gupta

Honors Theses

Flow separation is a phenomenon that occurs when pressure increases in the streamwise direction of a flow, making a distinctive boundary layer or separation bubble. It causes aircraft to experience an increase in drag and noise and a decrease in a lift, hence degrading their aviation performance. This study uses numerical simulations to understand better the effects of high-frequency translational surface actuation (HFTSA) on flow separation control. The numerical simulations mimic the experimental parameters of an experiment performed by Okoye et al. on using the HFTSA system to control flow separation. A symmetrical airfoil structure of chord length of 0.3 …


A Comparative Study Between 6 Degree-Of-Freedom Trajectory Model And Modified Point Mass Trajectory Model Of Spinning Projectiles, Ange Du 2021 Embry-Riddle Aeronautical University

A Comparative Study Between 6 Degree-Of-Freedom Trajectory Model And Modified Point Mass Trajectory Model Of Spinning Projectiles, Ange Du

Doctoral Dissertations and Master's Theses

For spinning projectiles, the 6 Degree-of-Freedom model can closely capture their trajectories with high accuracy and details. However, it comes with the drawbacks of long computation time and needing many aerodynamic coefficients which can be hard to obtain. The Modified Point Mass Trajectory Model was introduced as a simplified solution. This work compares them with each other, and with some more conventional methods. A program is developed to simulate and visualize trajectories. With some augmentations, the Modified Point Mass model is able to generate comparable results in most cases, but not including special cases such as when the projectile is …


Project G.H.O.S.T., Matthew Morell, Austin Conrad, Zackeris Gordon, Conan Estes 2021 California Polytechnic State University, San Luis Obispo

Project G.H.O.S.T., Matthew Morell, Austin Conrad, Zackeris Gordon, Conan Estes

Mechanical Engineering

Project G.H.O.S.T aimed to produce a model transmission with a control system for high performance/racing electric vehicles to utilize the full capability of the electric motor at higher speed applications. Current electric vehicles have a large amount of torque and use a fixed gear ratio that compromises between both high and low speeds with performance peaking around 65 miles per hour. A typical electric motor used in this application has approximately 1800 ft-lbs of torque up to 5,000 rpm. Past approximately 5,000 rpm, the torque rapidly drops off and so does the overall vehicle performance. Though transmissions exist that could …


Accelerated Controller Tuning For Wind Turbines Under Multiple Hazards, Aly Mousaad Aly, Milad Rezaee 2021 Louisiana State University

Accelerated Controller Tuning For Wind Turbines Under Multiple Hazards, Aly Mousaad Aly, Milad Rezaee

Faculty Publications

During their lifecycle, wind turbines can be subjected to multiple hazard loads, such as high-intensity wind, earthquake, wave, and mechanical unbalance. Excessive vibrations, due to these loads, can have detrimental effects on energy production, structural lifecycle, and the initial cost of wind turbines. Vibration control by various means, such as passive, active, and semi-active control systems provide crucial solutions to these issues. We developed a novel control theory that enables semi-active controller tuning under the complex structural behavior and inherent system nonlinearity. The proposed theory enables the evaluation of semi-active controllers’ performance of multi-degrees-of-freedom systems, without the need for time-consuming …


A Feedback-Based Pneumatic Compression System For Effective Lymphedema Management, Mohammad Imrul Kayes 2021 Louisiana State University

A Feedback-Based Pneumatic Compression System For Effective Lymphedema Management, Mohammad Imrul Kayes

LSU Master's Theses

Bioimpedance analysis (BIA) is a method of detecting lymphedema- a debilitating medical condition involving swelling of the extremities. Pneumatic compression devices are frequently used in the compression treatment of lymphedema. Although existing compression technology provides relief of symptoms, it has limitations in terms of ease-of-use, portability, and monitoring of treatment progress. Currently, there are no BIA analyzers in the market that run on a low-power microcontroller and a rechargeable battery. Moreover, no such device currently exists that integrate the BIA analysis with pneumatic compression system to offer a feedback-based solution for lymphedema treatment. This work represents the first steps towards …


A Single-Stage Passive Vibration Isolation System For Scanning Tunneling Microscopy, Toan T. Le 2021 California Polytechnic State University, San Luis Obispo

A Single-Stage Passive Vibration Isolation System For Scanning Tunneling Microscopy, Toan T. Le

Master's Theses

Scanning Tunneling Microscopy (STM) uses quantum tunneling effect to study the surfaces of materials on an atomic scale. Since the probe of the microscope is on the order of nanometers away from the surface, the device is prone to noises due to vibrations from the surroundings. To minimize the random noises and floor vibrations, passive vibration isolation is a commonly used technique due to its low cost and simpler design compared to active vibration isolation, especially when the entire vibration isolation system (VIS) stays inside an Ultra High Vacuum (UHV) environment. This research aims to analyze and build a single-stage …


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