Mechanical Engineering Commons^™

Effects Of Exciting And Relaxing Music On Heart Rate Variability, Pratik S. Mahajan

Honors Undergraduate Theses

Heart rate variability (HRV) and music have been demonstrated to have a relationship in previous literature. The primary objective of this study is to further investigate that relationship by observing HRV during periods of listening to relaxing and exciting music and comparing the results to a baseline as well as the other condition. The secondary objective of this study is to investigate the efficacy and potential usage of the Polar H10 chest strap monitor in measuring HRV parameters. The results of the Polar H10 will be compared to the iWorx TA-220 and iWorx-ECG12, the existing gold standard in HRV and …

Concentration Field Based Micropore Flow Rate Measurements, Matia P. Edwards, Samuel F. D. J. Gómez, Michael S. H. Boutilier

Chemical and Biochemical Engineering Publications

Demand is growing for a larger catalogue of experimental techniques to measure flow rates through micro-/nanoscale systems for both fundamental research and device development. Flow emerging from a hole in a plane wall is a common system of interest in such work for its relevance to membrane separation. In this paper, we consider the possibility of measuring volume flow rates through small scale orifice plates from images of dye dispersions downstream. Based on approximate analytical solutions to the advection–diffusion equation, we show that, at low Reynolds numbers, the concentration in the nearly hemispherical plume that forms increases linearly with inverse …

An Efficient And Low-Cost Method To Create High-Density Nitrogen-Vacancy Centers In Cvd Diamond For Sensing Applications., Prem Bahadur Karki, Rupak Timalsina, Mohammadjavad Dowran, Ayodimeji E. Aregbesola, Abdelghani Laraoui, Kapildeb Ambal

Department of Mechanical and Materials Engineering: Faculty Publications

The negatively charged Nitrogen-Vacancy (NV^-) center in diamond is one of the most versatile and robust quantum sensors suitable for quantum technologies, including magnetic field and temperature sensors. For precision sensing applications, densely packed NV^- centers within a small volume are preferable due to benefiting from 1/√𝑁 sensitivity enhancement (N is the number of sensing NV centers) and efficient excitation of NV centers. However, methods for quickly and efficiently forming high concentrations of NV^- centers are in development stage. We report an efficient, low-cost method for creating high-density NV^- centers production from a relatively …

Correction: Nanoscale Imaging Of Antiferromagnetic Domains In Epitaxial Films Of Cr2o3 Via Scanning Diamond Magnetic Probe Microscopy, Adam Erickson, Syed Qamar Abbas Shah, Ather Mahmood, Ilja Fescenko, Rupak Timalsina, Christian H. Binek, Abdelghani Laraoui

Department of Mechanical and Materials Engineering: Faculty Publications

Correction for ‘Nanoscale imaging of antiferromagnetic domains in epitaxial films of Cr2O3 via scanning diamond magnetic probe microscopy’ by Adam Erickson et al., RSC Adv., 2023, 13, 178–185, https:// doi.org/10.1039/D2RA06440E

Traversing With Quantitative Fidelity Through The Glass Transition Of Amorphous Polymers: Modeling The Thermodynamic Dilatational Flow Of Polycarbonate, Mehrdad Negahban, Wenlong Li, Jean-Marc Saiter, Laurent Delbreilh, Kyle Strabala, Zheng Li

Department of Mechanical and Materials Engineering: Faculty Publications

We follow the assumption that the dilatational response of glassy polymers can be characterized by a back-stress type analog that includes a thermal expansion for each elastic component, and with a viscosity that is dependent on the expansion of the elastic back stress component. To this, we add the assumption of an unloaded equilibrium temperature that correlates to the past processing through the viscous flow. After setting this in a thermodynamically consistent structure, the elastic, elastic backstress, thermal expansion, back-stress thermal expansion, heat capacity and viscous damping are evaluated using existing experiments for the response of polycarbonate over the glassy …

Evaluation And Optimization Of Thermal Solutions In Air And Liquid Cooling Systems For Datacenters, Vibin Shalom Simon

Mechanical and Aerospace Engineering Dissertations - Archive

A data center is a specifically constructed establishment designed to accommodate computing, storage, and transmission equipment, thereby facilitating essential business operations spanning diverse sectors of the economy. This facility serves as the designated physical infrastructure for housing servers, networking components, and data storage systems. In the context of traditional data centers, a substantial portion of energy, specifically around 45% to 55%, is directed towards supporting information technology (IT) operations. Additionally, a considerable allocation, varying from 30% to 40%, is attributed to the facilitation of cooling processes. The scope of this dissertation study comprises nine distinct chapters, each contributing to addressing …

Non-Intrusive Reduced Order Model Formulation For Inverse Shape Design Including Deforming Meshes And Multiphysics Problems., Kapil Aryal

Mechanical and Aerospace Engineering Dissertations - Archive

Despite significant advancements in computer capabilities for numerical simulations, engineers continue to face limitations when dealing with large-scale full-order model(FOM) simulations. These simulations often necessitate repeated solves, such as those encountered in inverse design, real-time solution prediction, error quantification, and solver convergence, among others. To address these challenges, reduced order modeling (ROM) has emerged as a valuable approach. This thesis focuses on the development of an ROM framework that combines Proper Orthogonal Decomposition (POD) with machine learning techniques. This integrated approach is applied to a diverse range of heat transfer and fluid flow inverse design problems. POD constructs optimal sets …

Cooperative Manipulation And Formation Control Using Multiple Aerial Vehicles, Uluhan Cem Kaya

Mechanical and Aerospace Engineering Dissertations - Archive

Recent advancements in autonomous systems have significantly impacted both academia and industry, opening new research avenues. One of them is the collaboration of multiple systems to achieve a common goal, which is known as a cooperative system. In the lack of human intelligence, decision making and perception capabilities, uncrewed autonomous systems could mutually benefit from each other’s capabilities when they are deployed and utilized together. This research tackles the collaboration of group of uncrewed aerial systems (UASs) where the constraint on individual vehicles requires a varying level of coordination and cooperation. Such cooperation can be in the form of a …

Turbulent Shockwave/Boundary-Layer Interactions Generated By Sharp Swept Fins, Dustin Levi Otten

Mechanical and Aerospace Engineering Dissertations - Archive

The shock/turbulent boundary layer interaction (STBLI) generated by a sharp fin with a 60 deg leading edge sweep mounted above a flat plate at Mach 2.5 was studied numerically. Incipient separation due to this highly swept fin was determined by varying the fin angle to the incoming freestream. The effect of a small fin/plate gap on STBLI incipient separation was established. Sweeping the fin increases the deflection required for incipient separation as the sweep reduces the interaction strength. A gap causes flow leakage under the fin, further reducing the interaction strength on the windward side. The incipient angle of attack …

Experimental Study On Thermal Performance Of Metal Foam Heat Sinks In Single Phase Liquid Immersion Cooling, Manish Kumawat

Mechanical and Aerospace Engineering Theses - Archive

In 1965, Intel co-founder Gordon Moore made the observation that the transistor counts on a chip double with a frequency of approximately every two years. This development resulted in more compact and potent ICs. However, the amount of heat produced on a chip increased proportionally with the number of transistors. Later, in the early 2000s, Dennard Scaling broke down. Transistors became so small that leakage currents (unwanted currents that flow within the transistor) emerged as a significant issue, and they contributed substantially to power consumption and heat generation. These tightly packed transistors produced heat, which decreased their performance and shortened …

Rc Baja - Drivetrain And Chassis, Sean Drake

All Undergraduate Projects

The ASME RC Baja competition is an event held every year where mechanical engineering technology students get a chance to use their accumulated knowledge of engineering and the engineering process to design and build an RC car to compete against one another at the event. The students of Central Washington University participating in the event were paired up into teams of two to work on a car. This report will discuss the drivetrain and chassis of the car, the suspension and steering were the responsibility of the project engineer Tanner Howington.

The project included the design and analysis of the …

Rc Baja Drivetrain & Chassis, John Lange

All Undergraduate Projects

This project is centered around the development of the drivetrain and chassis for a 1/10th scale RC Baja vehicle capable of withstanding loads over the course of an RC Baja competition consisting of a solemn, drag race, and challenge course while maintaining high speeds and short acceleration times.

This project utilized 3D printing and CNC manufacturing techniques to produce a lightweight frame and efficient drivetrain. A 3800 KV brushless motor drives a two stage gearbox, which transfers force to a 90 degree locked differential to produce high torque and even application of force at low motor RPM. To support the …

R/C Baja, Tanner Howington

All Undergraduate Projects

The ASME RC Baja competition derives a need for an RC car capable of performing at a competitive level in Slalom, Sprint, and Offroad racing. To accomplish this task a suspension and steering system was designed to limit the weight of the components without compromising the structural strength, which resulted in optimizing the overall speed and stability of the vehicle. The responsibilities for optimizing the drivetrain and chassis were handled by co-engineer Sean Drake.

To ensure that each component of the suspension and steering system would hold when subjected to the expected forces, various stress analyses were performed to the …

Nasa Student Rocket Launch, Ethan Stapleton

All Undergraduate Projects

The Rocketry Payload team consisting of Kallysta, Eli and Ethan needed to build a payload that flew in a rocket also built by the team. After the rocket has landed, a camera is deployed outside the rocket through a 3-inch gap created by a linear actuator. The camera must rotate 360 degrees and take photos of the surrounding area. The entire system must weigh less than 4.4 pounds as well. The team designed this system using their knowledge obtained through the Mechanical Engineering program at Central Washington University. It was important for them to keep in mind that the system …

Jcati Carbon Fiber Recycler: Crusher System, Devin Riley

All Undergraduate Projects

With a substantial rise in Carbon Fiber use across all industries, the need for a way to recycle the waste has grown as well. A group of Mechanical Engineering Technology students at Central Washington University funded by the Joint Center for Aerospace Technology (JCATI) have created a machine to recycle waste wing trimmings from the Boeing company’s airplanes. This machine consists of 5 different sub-assemblies being the oven, crusher, gear train, conveyor, and shredder. The purpose of this project was to decrease the deflection in the crusher caused by bulging in the housing and movement of the bearings. To decrease …

Rc Baja: Suspension And Steering, Baley Norton, John Lange

All Undergraduate Projects

Engineering students attending Central Washington University were tasked with developing and creating a functional RC car. This car would then compete in a state-wide competition while being developed over the course of three quarters with the competition being held in the spring. This was completed in teams of two that were assigned two of the four sections within this project who then independently designed and developed each section. This was broken down into having one teammate in charge of the drivetrain and chassis and having the other teammate working on the suspension and steering sections of the vehicle. Each section …

Semi-Robotic Knee Arthroscopy System With Braking Mechanism, Thai Hua

Honors Undergraduate Theses

To alleviate the poor ergonomics which surgeons suffer during knee arthroscopy, a semi-robotic device with braking mechanism is created for intraoperative assistance. A slitted ball joint assembly is developed to transmit the clamping force to the arthroscope inside. Ball deformation and stress at various angles to the vertical and clamping forces is recorded through Abaqus Finite Element Analysis (FEA). Contact forces between the scope and inner surfaces of the ball is also computed in FEA at different clamping forces. The von Mises stress occurring in the ball joint is under the yield stress limit for polyethylene, and there is noticeable …

Effectiveness Of Acoustic Design In Public Spaces, Jana V. Jirgens

Honors Undergraduate Theses

In this thesis, a discussion on the effectiveness of acoustic design in public spaces is made. The auditory properties of a location have noteworthy implications on the success of a building's design and how a room is perceived. Depending on the requirements of each location, either a reverberant or sound-absorbing approach is best suited for the environment. Moreover, public health is negatively affected by long-term involuntary noise exposure. Because of this, there is an obvious demand for continued and expanded study in acoustic design. This thesis aims to challenge interior design choices made in four testing locations: a classroom, a …

Timken Black Oxide False Brinelling Project, Elizabeth Kotzalas

Williams Honors College, Honors Research Projects

There is a known issue that occurs in wind turbine main shaft bearings, among other bearing types and applications during transportation or while the turbine is powered on, but the bearing is not spinning. This issue is damage that is confined to mostly the raceways but can damage the rollers over time. It is called false brinelling and is a material removal from the raceways due to repeated tiny vibrations of the rollers over the same area. A question was posed on whether black oxide surface treatment could reduce false brinelling wear on bearings in this application, and as a …

Multi-Material 3d Printing With Hybrid Direct Ink Writing-Volumetric Additive Manufacturing (Diw-Vam) System, Jose Zapata

Electronic Theses and Dissertations, 2020-2023

The rapid growth of 3D printing has led to many new iterations of additive manufacturing techniques. However, the current 3D printing techniques encompass only one printing method and have gradually expanded the ability to print multiple materials simultaneously. In this research, a hybrid 3D printing system is created by integrating direct ink writing (DIW) into volumetric additive manufacturing (VAM) to achieve multi-material printing. Compared to traditional DLP and SLA printing systems, the hybrid DIW-VAM system can create parts 95% faster. Meanwhile, the developed hybrid system takes advantages of DIW's precision to suspend a secondary liquid resin through extrusion into a …

A Conceptual Model For Quality 4.0 Deployment In U.S. Based Manufacturing Firms, Thomas Jones

Electronic Theses and Dissertations, 2020-2023

Manufacturing is currently undergoing a fourth industrial revolution, referred to as Industry 4.0, enabled by digital technologies and advances in our ability to collect and use data. Quality 4.0 is the application of Industry 4.0 to enhance the quality function within an organization. Quality practitioners are uniquely positioned within organizations and already possess data application skillsets. Despite a perception that Quality 4.0 will be critical to future success shared by a majority of industry, most companies have not attempted to implement Quality 4.0 strategy, and those that have report very low rates of success. The goal of this study was …

Design And Simulation Analysis Of A Bipv (Building Integrated With Pv) Air-Duct System For Residential High-Performance Development, Arash Zarmehr

Electronic Theses and Dissertations, 2020-2023

A growing number of buildings are integrating building-integrated photovoltaics (BIPV) devices to increase energy efficiency and reduce energy costs. A building's heating and cooling loads are impacted by the thermal resistance of the air duct BIPV because of the change in thermal resistance. Therefore, augmenting the efficiency of (BIPV) devices will benefit many building architectures and mechanical engineering applications. This work introduces a low-cost and low- maintenance air duct system design augmenting BIPV systems. This novel approach increases airflow velocity and decreases air temperature for BIPV, resulting in improved performance for the PV system electricity output, increased PV lifespan due …

Strategies To Increase Competitive Advantage In The Automotive Manufacturing Supply Chain, Amber Willis

Walden Dissertations and Doctoral Studies

Some automotive manufacturing supply chain leaders lack strategies that are needed to implement information technology (IT) systems. Business leaders are concerned with implementing IT systems to achieve and maintain a competitive advantage. Grounded in the resource-based view theory (RBV), the purpose of this qualitative single case study was to explore information system strategies used by leaders in the automotive manufacturing supply chain to achieve competitive advantage. Participants were five leaders of an automotive manufacturing supply chain organization who implemented IT systems. Data were collected through semistructured interviews and a review of organization project documents. Through thematic analysis, five themes were …

A Methodology For Statistical Mean Wave Climate Regime Characterisation In Oceanic Islands: The Case Of The Southern Coast Of Tenerife, Emilio Megías, Manuel García-Román

Journal of Marine Science and Technology–Taiwan

Oceanic islands of volcanic origin tend to have peculiar characteristics, such as: exposure to many wave directions; grouping in archipelagos; steep coastal slopes; and small coastal shelves. All these features require certain considerations in wave climate studies. These types of studies, when wave spectra are not available and have to be performed with parametric data, can be unreliable without an adequate systematic treatment. In this work we propose a methodology consisting of pre-classification according to the peak period and subsequent separation into different sectors according to the geographical fetch. The island of Tenerife is the case study, and in particular …

Method-Of-Characteristics Models For Flowfield Evaluation Of Hypervelocity Test Facilities, Ananthkumar Jayamani

Mechanical and Aerospace Engineering Dissertations - Archive

Ground test facilities are an imperative part of the design and development of flying vehicles. In the case of high-enthalpy facilities, evaluating the gasdynamic and thermochemical state of the test gas poses challenges due to high temperature effects. This study aims to contribute to the development impulse facilities by developing reduced-order models resolving the flowfields of such facilities. Developed as a part of this study are various method-of-characteristics (MoC) algorithms which consider gases under varying levels of thermochemical complexity. The algorithms span from simple calorically perfect gases to full thermochemical nonequilibrium. The first set of algorithms was limited to unsteady …

Microstructural Finite Element Modeling Of High-Performance Carbon Fiber-Reinforced Composites To Characterize Microscale Material Properties And Fiber-Direction Compressive Strength, Quy Tung Ling Vu

Mechanical and Aerospace Engineering Dissertations - Archive

Carbon fiber-reinforced composites are increasingly used in aerospace application thanks to their excellent specific stiffness and strength. However, incomplete understanding of their failure behaviors leads to composite components often being designed with a high Safety Factor, limiting their advantages. Using computational methods, this project studies carbon fiber-reinforced composite microstructures for the objective of understanding and improving material performances under compression load which is one of the main considerations in primary aerospace structure design. A Finite Element (FE) model for the evaluation of composite compression behaviors was developed, allowing the identification of several key material properties affecting composite performance. The numerical …

Cooperative Rendezvous In Multi-Vehicle Systems, Rajeev Shobhit Voleti

Mechanical and Aerospace Engineering Dissertations - Archive

The field of cooperative, multi-vehicle systems has witnessed a significant expansion and evolution, yielding considerable opportunities for improved autonomy, resilience, and robustness. Despite these promising developments, complex challenges persist in ensuring secure and efficient rendezvous among cooperative peers. The term "rendezvous," within the realm of cooperative control, refers to the simultaneous convergence of multi-vehicle systems to a designated target location. In missile guidance, the problem of multiple pursuer missiles achieving rendezvous with a target is termed as a salvo attack. Current methodologies often grapple with issues related to synchronization, high latency and network security, all of which can adversely impact …

A Rigid Body Framework For Modeling And Simulation Of Formation Of Autonomous Agents, Suguru Sato

Mechanical and Aerospace Engineering Theses - Archive

Formation motion, wherein multiple agents operate within close proximity while maintaining precise relative positions and coordinated movements has a significant impact in the realm of Uncrewed Aerial Systems (UAS). Formation establishment, and station-keeping have been critical research areas as several missions can be conceived, and accomplished by groups of “simple” autonomous agents. Advances in this research have led to multiple advantages in areas such as reconnaissance, aerospace exploration, map building, search and rescue, etc. particularly, if the formation motion is inspired by nature and natural phenomena such as flock of birds, school of fish, hydrodynamics (smooth streamlines), magnetic fields, and …

Effect Of Autoclave Process Parameters On Mechanical Behaviors Of Carbon Fiber Reinforced Polymer Composites Fabricated Via Additive Manufacturing, Quang Hao Nguyen

Honors Undergraduate Theses

Additively manufactured carbon fiber reinforced polymers (CFRP) are vastly studied for their remarkable mechanical properties compared to most other 3D printed materials. Different methods were employed to further increase mechanical performance of CFRP 3D printed parts. The objective of the study is to investigate the effect of autoclave postprocessing on the interlaminar shear behavior between 3D printed CFRP layers. 3D printed CFRP samples were processed with nine combinations of temperature and vacuum in an autoclave. Short beam shear (SBS) tests were performed to characterize the interlaminar shear strength (ILSS) of the samples after autoclave processing. Digital image correlation (DIC) was …

Variational Autoencoder And Sensor Fusion For Robust Myoelectric Controls, Keith A. Currier

Honors Undergraduate Theses

Myoelectric control schemes aim to utilize the surface electromyography (EMG) signals which are the electric potentials directly measured from skeletal muscles to control wearable robots such as exoskeletons and prostheses. The main challenge of myoelectric controls is to increase and preserve the signal quality by minimizing the effect of confounding factors such as muscle fatigue or electrode shift. Current research in myoelectric control schemes are developed to work in ideal laboratory conditions, but there is a persistent need to have these control schemes be more robust and work in real-world environments. Following the manifold hypothesis, complexity in the world can …