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Description
Microgrids are a subset of the modern power structure; using distributed generation (DG) to supply power to communities rather than vast regions. The reduced scale mitigates loss allowing the power produced to do more with better control, giving greater security, reliability, and design flexibility. This paper explores the performance and

Microgrids are a subset of the modern power structure; using distributed generation (DG) to supply power to communities rather than vast regions. The reduced scale mitigates loss allowing the power produced to do more with better control, giving greater security, reliability, and design flexibility. This paper explores the performance and cost viability of a hybrid grid-tied microgrid that utilizes Photovoltaic (PV), batteries, and fuel cell (FC) technology. The concept proposes that each community home is equipped with more PV than is required for normal operation. As the homes are part of a microgrid, excess or unused energy from one home is collected for use elsewhere within the microgrid footprint. The surplus power that would have been discarded becomes a community asset, and is used to run intermittent services. In this paper, the modeled community does not have parking adjacent to each home allowing for the installment of a privately owned slower Level 2 charger, making EV ownership option untenable. A solution is to provide a Level 3 DC Quick Charger (DCQC) as the intermittent service. The addition of batteries and Fuel Cells are meant to increase load leveling, reliability, and instill limited island capability.
ContributorsPatterson, Maxx (Author) / Madakannan, Arunachalanadar (Thesis advisor) / Macia, Narciso (Committee member) / Peng, Xihong (Committee member) / Arizona State University (Publisher)
Created2013
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Description
Dye sensitized solar cells (DSSCs) are the third generation solar cells expected to outperform the first two generations of solar cells with their advantages of comparative higher efficiency and lower manufacturing costs. The manufacturing cost of Dye sensitized solar cells is one fifth of the conventional silicon solar cell. However,

Dye sensitized solar cells (DSSCs) are the third generation solar cells expected to outperform the first two generations of solar cells with their advantages of comparative higher efficiency and lower manufacturing costs. The manufacturing cost of Dye sensitized solar cells is one fifth of the conventional silicon solar cell. However, DSSCs have problems of low conversion efficiency, stability and reliability. Some effective approaches are required to improve their performance. This paper projects the work related to assessment and verification of the repeatability of the semi-automated fabrication process. Changes were introduced in to the fabrication process to enhance the efficiency and stability. The sealant step in the fabrication process was remodeled to a newer version with an improvement in efficiency from 11% to 11.8%. Sputtering was performed on counter electrode in 30 seconds intervals. Cells were fabricated to assess the performance & time dependent characteristics from EIS experiments. Series resistance increased three times in sputtered Pt electrode as compared to standard platinum electrode. This resulted in the degradation of conductive surface on glass electrode due to heavy bombardment of ions. The second phase of the project work relates to the incorporation of SWCNT on the TiO2 electrode and its effect on the cell efficiency. Different weight loadings (0.1 wt %, 0.2 wt%, 0.4 wt %) of SWCNTs were prepared and mixed with the commercial TiO2 paste and ethanol solvent. The TiO2-SWCNT layer was coated on the electrode using screen-printing technique. Both open circuit voltage and photocurrent were found to have measurable dependence on the TiO2 layer loading. Photo voltage ranged from ~0.73 V to ~0.43 V and photocurrent from ~8 to ~33 mA depending on weight percent loading. This behavior is due to aggregation of particles and most TiO2 aggregate particles are not connected to SWCNT. Transparency loss was observed leading to saturation in the photo current and limiting the light absorption within the TiO2 film.
ContributorsKinhal, Kartik (Author) / Munukutla, Lakshmi V (Thesis advisor) / Subach, James (Committee member) / Peng, Xihong (Committee member) / Arizona State University (Publisher)
Created2011
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Description
The field of robotics is rapidly expanding, and with it, the methods of teaching and introducing students must also advance alongside new technologies. There is a challenge in robotics education, especially at high school levels, to expose them to more modern and practical robots. One way to bridge this ga

The field of robotics is rapidly expanding, and with it, the methods of teaching and introducing students must also advance alongside new technologies. There is a challenge in robotics education, especially at high school levels, to expose them to more modern and practical robots. One way to bridge this gap is human-robot interaction for a more hands-on and impactful experience that will leave students more interested in pursuing the field. Our project is a Robotic Head Kit that can be used in an educational setting to teach about its electrical, mechanical, programming, and psychological concepts. We took an existing robot head prototype and further advanced it so it can be easily assembled while still maintaining human complexity. Our research for this project dove into the electronics, mechanics, software, and even psychological barriers present in order to advance the already existing head design. The kit we have developed combines the field of robotics with psychology to create and add more life-like features and functionality to the robot, nicknamed "James Junior." The goal of our Honors Thesis was to initially fix electrical, mechanical, and software problems present. We were then tasked to run tests with high school students to validate our assembly instructions while gathering their observations and feedback about the robot's programmed reactions and emotions. The electrical problems were solved with custom PCBs designed to power and program the existing servo motors on the head. A new set of assembly instructions were written and modifications to the 3D printed parts were made for the kit. In software, existing code was improved to implement a user interface via keypad and joystick to give students control of the robot head they construct themselves. The results of our tests showed that we were not only successful in creating an intuitive robot head kit that could be easily assembled by high school students, but we were also successful in programming human-like expressions that could be emotionally perceived by the students.
ContributorsRathke, Benjamin (Co-author) / Rivera, Gerardo (Co-author) / Sodemann, Angela (Thesis director) / Itagi, Manjunath (Committee member) / Engineering Programs (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
Description
The field of soft robotics is a very quickly growing field that has yet to be fully explored or implemented in all of the possible applications. Soft robotics shows the greatest degree of possibility for mimicking biological systems effectively and accurately. This study seeks to set the groundwork for the

The field of soft robotics is a very quickly growing field that has yet to be fully explored or implemented in all of the possible applications. Soft robotics shows the greatest degree of possibility for mimicking biological systems effectively and accurately. This study seeks to set the groundwork for the development of a biomimetic nautilus using soft robotic methods. The study shows background research and discusses the methods used to develop a nautilus themed sub aquatic robot that uses a double bladder system and a pump to generate thrust for movement. The study shows how the unit would be fabricated and constructed. The study also explores why the second stage of the design failed and how it could potentially be fixed in future iterations.
ContributorsCarlson, Caleb Elijah (Author) / Polygerinos, Panagiotis (Thesis director) / Parsey, John (Committee member) / Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2017-05
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Description
The goal of our research was to develop and validate a method for predicting the mechanical behavior of Additively Manufactured multi-material honeycomb structures. Multiple approaches already exist in the field for modeling the behavior of cellular materials, including the bulk property assumption, homogenization and strut level characterization [1]. With the

The goal of our research was to develop and validate a method for predicting the mechanical behavior of Additively Manufactured multi-material honeycomb structures. Multiple approaches already exist in the field for modeling the behavior of cellular materials, including the bulk property assumption, homogenization and strut level characterization [1]. With the bulk property approach, the structure is assumed to behave according to what is known about the material in its bulk formulation, without regard to its geometry or scale. With the homogenization technique, the specimen that is being tested is treated as a solid material within the simulation environment even if the physical specimen is not. Then, reduced mechanical properties are assigned to the specimen to account for any voids that exist within the physical specimen. This approach to mechanical behavior prediction in cellular materials is shape dependent. In other words, the same model cannot be used from one specimen to the next if the cell shapes of those lattices differ in any way. When using the strut level characterization approach, a single strut (the connecting member between nodes constituting a cellular material) is isolated and tested. With this approach, there tends to be a significant deviation in the experimental data due to the small size of the isolated struts. Yet it has the advantage of not being shape sensitive, at least in principle. The method that we developed, and chose to test lies within the latter category, and is what we have coined as the Representative Lattice Element (RLE) Method. This method is modeled after the well-established Representative Volume Element (RVE) method [2]. We define the RLE as the smallest unit over which mechanical tests can be conducted that will provide results which are representative of the larger lattice structure. In other words, the theory is that a single member (or beam in this case) of a honeycomb structure can be taken, tests can be conducted on this member to determine the mechanical properties of the representative lattice element and the results will be representative of the mechanical behavior whole structure. To investigate this theory, we designed specimens, conducted various tensile and compression tests, analyzed the recorded data, conducted a micromechanics study, and performed structural simulation work using commercial Finite Element Analysis software.
ContributorsSalti, Ziyad Zuheir (Co-author) / Eppley, Trevor (Co-author) / Bhate, Dhruv (Thesis director) / Song, Kenan (Committee member) / Engineering Programs (Contributor) / Barrett, The Honors College (Contributor)
Created2018-05
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Description
Proton exchange membrane fuel cells (PEMFCs) run on pure hydrogen and oxygen (or air), producing electricity, water, and some heat. This makes PEMFC an attractive option for clean power generation. PEMFCs also operate at low temperature which makes them quick to start up and easy to handle. PEMFCs have several

Proton exchange membrane fuel cells (PEMFCs) run on pure hydrogen and oxygen (or air), producing electricity, water, and some heat. This makes PEMFC an attractive option for clean power generation. PEMFCs also operate at low temperature which makes them quick to start up and easy to handle. PEMFCs have several important limitations which must be overcome before commercial viability can be achieved. Active areas of research into making them commercially viable include reducing the cost, size and weight of fuel cells while also increasing their durability and performance. A growing and important part of this research involves the computer modeling of fuel cells. High quality computer modeling and simulation of fuel cells can help speed up the discovery of optimized fuel cell components. Computer modeling can also help improve fundamental understanding of the mechanisms and reactions that take place within the fuel cell. The work presented in this thesis describes a procedure for utilizing computer modeling to create high quality fuel cell simulations using Ansys Fluent 12.1. Methods for creating computer aided design (CAD) models of fuel cells are discussed. Detailed simulation parameters are described and emphasis is placed on establishing convergence criteria which are essential for producing consistent results. A mesh sensitivity study of the catalyst and membrane layers is presented showing the importance of adhering to strictly defined convergence criteria. A study of iteration sensitivity of the simulation at low and high current densities is performed which demonstrates the variance in the rate of convergence and the absolute difference between solution values derived at low numbers of iterations and high numbers of iterations.
ContributorsArvay, Adam (Author) / Madakannan, Arunachalanadar (Thesis advisor) / Peng, Xihong (Committee member) / Liang, Yong (Committee member) / Subach, James (Committee member) / Arizona State University (Publisher)
Created2011
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Description

Lithium ion batteries are quintessential components of modern life. They are used to power smart devices — phones, tablets, laptops, and are rapidly becoming major elements in the automotive industry. Demand projections for lithium are skyrocketing with production struggling to keep up pace. This drive is due mostly to the

Lithium ion batteries are quintessential components of modern life. They are used to power smart devices — phones, tablets, laptops, and are rapidly becoming major elements in the automotive industry. Demand projections for lithium are skyrocketing with production struggling to keep up pace. This drive is due mostly to the rapid adoption of electric vehicles; sales of electric vehicles in 2020 are more than double what they were only a year prior. With such staggering growth it is important to understand how lithium is sourced and what that means for the environment. Will production even be capable of meeting the demand as more industries make use of this valuable element? How will the environmental impact of lithium affect growth? This thesis attempts to answer these questions as the world looks to a decade of rapid growth for lithium ion batteries.

ContributorsMelton, John (Author) / Brian, Jennifer (Thesis director) / Karwat, Darshawn (Committee member) / Chemical Engineering Program (Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description
The CNC mill is a highly valuable tool for engineering design, allowing for the creation of precise and complex metal parts. However, due to their high cost, many engineers do not have access to these machines until they enter industry, limiting the knowledge and experience of engineering students. This also

The CNC mill is a highly valuable tool for engineering design, allowing for the creation of precise and complex metal parts. However, due to their high cost, many engineers do not have access to these machines until they enter industry, limiting the knowledge and experience of engineering students. This also restricts the level of engineering design they can participate in as they are limited to lower strength materials and processes. To expand the possibilities for engineering students, hobbyists, and small businesses, we created a reliable and affordable desktop CNC mill. Our machine is capable of cutting non-ferrous metals such as aluminum with 70μm repeatable part precision and be compatible with coolant and vacuum systems.
ContributorsHodson, Kenneth (Author) / Altobelli, Seth (Co-author) / Jordan, Shawn (Thesis director) / Sweeney, Rhett (Committee member) / Barrett, The Honors College (Contributor) / Engineering Programs (Contributor)
Created2023-05
Description

Cornhole, traditionally seen as tailgate entertainment, has rapidly risen in popularity since the launching of the American Cornhole League in 2016. However, it lacks robust quality control over large tournaments, since many of the matches are scored and refereed by the players themselves. In the past, there have been issues

Cornhole, traditionally seen as tailgate entertainment, has rapidly risen in popularity since the launching of the American Cornhole League in 2016. However, it lacks robust quality control over large tournaments, since many of the matches are scored and refereed by the players themselves. In the past, there have been issues where entire competition brackets have had to be scrapped and replayed because scores were not handled correctly. The sport is in need of a supplementary scoring solution that can provide quality control and accuracy over large matches where there aren’t enough referees present to score games. Drawing from the ACL regulations as well as personal experience and testimony from ACL Pro players, a list of requirements was generated for a potential automatic scoring system. Then, a market analysis of existing scoring solutions was done, and it found that there are no solutions on the market that can automatically score a cornhole game. Using the problem requirements and previous attempts to solve the scoring problem, a list of concepts was generated and evaluated against each other to determine which scoring system design should be developed. After determining that the chosen concept was the best way to approach the problem, the problem requirements and cornhole rules were further refined into a set of physical assumptions and constraints about the game itself. This informed the choice, structure, and implementation of the algorithms that score the bags. The prototype concept was tested on their own, and areas of improvement were found. Lastly, based on the results of the tests and what was learned from the engineering process, a roadmap was set out for the future development of the automatic scoring system into a full, market-ready product.

ContributorsGillespie, Reagan (Author) / Sugar, Thomas (Thesis director) / Li, Baoxin (Committee member) / Barrett, The Honors College (Contributor) / Engineering Programs (Contributor) / Dean, W.P. Carey School of Business (Contributor)
Created2023-05
Description

Our project is to create a simplified, portable, modular electrocardiogram known as ECG/EKG. Most medical facilities, including hospitals, clinics, and skilled nursing facilities, still rely on traditional 12-lead EKG equipment consisting of a large cart with long 10 wires. These wires can be a pain to constantly detangle and rearrange

Our project is to create a simplified, portable, modular electrocardiogram known as ECG/EKG. Most medical facilities, including hospitals, clinics, and skilled nursing facilities, still rely on traditional 12-lead EKG equipment consisting of a large cart with long 10 wires. These wires can be a pain to constantly detangle and rearrange to determine a person’s heart conditions. This creates issues in fast paced scenarios such as when a patient is experiencing a heart attack and needs an EKG stat. Additionally, the current technology can be somewhat unreliable at determining heart conditions, causing providers to request multiple EKG’s for patients. With our improved versatile EKG, we can help solve these issues and implement additional outpatient use with its portable features. This can be done by remotely monitoring heart conditions during activities such as exercise, sleep, or stressful events, without worrying about wire disturbance.

ContributorsMullins, Hunter (Author) / Lam, Jadon (Co-author) / Goode, Zachary (Co-author) / Taut, Sarah (Co-author) / Lee, Youngju (Co-author) / Huang, Hai (Co-author) / Byrne, Jared (Thesis director) / Swader, Melissa (Committee member) / McElfish, Alex (Committee member) / Barrett, The Honors College (Contributor) / Engineering Programs (Contributor)
Created2023-05