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2020

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Full-Text Articles in Mechanical Engineering

Design, Fabrication, And Reliability Effects Of Additively Manufactured First Level Compliant Interconnects For Microelectronics Application, Tumininu David Olatunji Dec 2020

Design, Fabrication, And Reliability Effects Of Additively Manufactured First Level Compliant Interconnects For Microelectronics Application, Tumininu David Olatunji

Graduate Theses and Dissertations

Semiconductor packaging and development is greatly dependent on the magnitude of interconnect and on-chip stress that ultimately limits the reliability of electronic components. Thermomechanical related strains occur because of the coefficient of thermal expansion mismatch from different conjoined materials being assembled to manufacture a device. To curb the effect of thermal expansion mismatch between conjoined parts, studies have been done in integrating compliant structures between dies, solder balls, and substrates. Initial studies have enabled the design and manufacturing of these structures using a photolithography approach which involves a high number of fabrication steps depending on the complexity of the structures …


Detailed Modeling Of The Flash Hydrolysis Of Algae For Biofuel-Production In Comsol Multiphysics, Noah Joseph Legrand Dec 2020

Detailed Modeling Of The Flash Hydrolysis Of Algae For Biofuel-Production In Comsol Multiphysics, Noah Joseph Legrand

Mechanical & Aerospace Engineering Theses & Dissertations

Algae-derived biofuels are being commercialized as an important renewable energy source. Like any new technology, conversion improvements are desired, including reductions in process complexity and better utilization of the entire microalgae feedstock. The Old Dominion Biomass Laboratory has focused on flash hydrolysis for algae biofuel production. That process involves rapidly heating algae and water mixed as a slurry to a subcritical state. Results from small-scale bench tests are promising, but process scale up is a challenge. Currently there exists a pilot laboratory scale system utilizing induction heating in order to reach controlled reaction temperatures with a reaction duration of 10 …


Hardware Development For The Generation Of Large-Volume High Pressure Plasma By Spatiotemporal Control Of Space Charge, Nikhil Boothpur Dec 2020

Hardware Development For The Generation Of Large-Volume High Pressure Plasma By Spatiotemporal Control Of Space Charge, Nikhil Boothpur

Electrical & Computer Engineering Theses & Dissertations

While generating a plasma under laboratory conditions, any attempt to scale the pressure and volume leads to instabilities due to the build-up of localized space-charge. This poses a challenge in the design of the discharge chamber, type of excitation field, and the type of gas that is used in the discharge. This work investigates a spatially and temporally varying electric field to control the formation of space-charge in large-volume (greater than 5 mm in the smallest dimension) near atmospheric pressure. The simulations show that in a space-charge dominated transport, the charged species disperse both in azimuthal and radial directions in …


Field Testing The Effects Of Low Reynolds Number On The Power Performance Of The Cal Poly Wind Power Research Center Small Wind Turbine, John B. Cunningham Dec 2020

Field Testing The Effects Of Low Reynolds Number On The Power Performance Of The Cal Poly Wind Power Research Center Small Wind Turbine, John B. Cunningham

Master's Theses

This thesis report investigates the effects of low Reynolds number on the power performance of a 3.74 m diameter horizontal axis wind turbine. The small wind turbine was field tested at the Cal Poly Wind Power Research Center to acquire its coefficient of performance, p, vs. tip speed ratio, λ, characteristics. A description of both the wind turbine and test setup are provided. Data filtration and processing techniques were developed to ensure a valid method to analyze and characterize wind power measurements taken in a highly variable environment. The test results demonstrated a significant drop in the …


Energy Harvesting Using Flextensional Piezoelectric Energy Harvesters In Resonance And Off-Resonance Modes, Mohamed A. Shabara Aug 2020

Energy Harvesting Using Flextensional Piezoelectric Energy Harvesters In Resonance And Off-Resonance Modes, Mohamed A. Shabara

Mechanical & Aerospace Engineering Theses & Dissertations

Energy harvesting technologies are integrated into various modern devices and systems. These systems include Artificial Intelligence (AI) systems, Internet of Things (IoT), various types of energy harvesters are integrated in many engineering applications such as automotive, aerospace and ocean engineering. In order to develop a fully functioning stand-alone system, it is essential to integrate it with a built in power source such as a battery or a power generator. Also, in many situations, city power sources might not be available. Therefore, reliable, renewable and sustainable local power generators are desired. Piezoelectric energy harvesting (PEH) technologies, which are piezoelectric material-based devices, …


Reading Robot, Gillian Watts, Andrew Myers, Sabrinna Tan, Taylor Klein, Omeed Djassemi Jun 2020

Reading Robot, Gillian Watts, Andrew Myers, Sabrinna Tan, Taylor Klein, Omeed Djassemi

General Engineering

Presently, there is an insufficient availability of human experts to assist students in reading competency and comprehension. Our team’s goal was to create an improved socially assistive robot for use by therapists, teachers, and parents to help children and adults develop reading skills while they do not have access to specialists. HAPI is a socially assistive robot that we created with the goal of helping students practice their reading comprehension skills. HAPI enables a student to improve their reading skills without an educator present, while enabling educators to review the student's performance remotely. Design constraints included: physical size, weight, duration …


Raysun's Infrared Raisin Dryer, Lucas Kensinger, Saraith Aispuro, Joe Vanacore Jun 2020

Raysun's Infrared Raisin Dryer, Lucas Kensinger, Saraith Aispuro, Joe Vanacore

General Engineering

The RaySuns senior project team was tasked with lowering the drying costs of raisins for River Ranch Raisins. In doing so, we explored several options for cutting costs: utilizing automation and exploring new drying technologies were our primary focus. We eventually planned a modular infrared heating mechanism which would be easy to automate in future projects. After manufacturing and testing an infrared heating mechanism, it was found that infrared drying could significantly cut costs versus the previous natural gas fired dryer tunnels while leaving room for automation. The infrared dryer was also shown to have the potential to create high-quality …


Heavy Lift Drone, Sam Carhart, David Cooper, Luis Gaitan, Michael Kaliterna, Sami Lama, Paul Rogel-Herrera, Yuya Yabe Jun 2020

Heavy Lift Drone, Sam Carhart, David Cooper, Luis Gaitan, Michael Kaliterna, Sami Lama, Paul Rogel-Herrera, Yuya Yabe

Interdisciplinary Design Senior Theses

Despite the rapid rise in the number of drones in the past few years, there has been little work done to produce a drone that is optimized for the FAA' s 55 lb upper takeoff limit. This gap in the market is one that the Heavy Lift Drone (HLD) fills - a light-weight, higher payload capability, and inexpensive drone to be used in commercial applications - most notably irrigation monitoring. The HLD is a contra-rotating hexagonal configuration system featuring two levels of propellers that allow for larger propeller diameter and generate greater lift. After performing extensive finite element analyses and …


Automated Drone Calibration System, Jackie Kelly Jong-Mee Paik, Zach Nathan Richter, Tyler Wilson Van Den Berg, Ryan Alexander Zhan, Matthew Ward Carlson Jun 2020

Automated Drone Calibration System, Jackie Kelly Jong-Mee Paik, Zach Nathan Richter, Tyler Wilson Van Den Berg, Ryan Alexander Zhan, Matthew Ward Carlson

Mechanical Engineering

The final design review of the Inspired Flight Calibration Team senior project will detail the process used to complete a verification prototype of a drone calibration device and discuss lessons learned and suggestions for improving this device. Going from brainstorming and conceptual prototyping all the way through verification prototyping and testing, we were able to design a gyroscopic device that met Inspired Flight’s needs for the flight sensor calibration of their drones. The mechanical design involved comprehensive CAD models and hands-on manufacturing. The mechatronics side of the project worked heavily with electrical wiring and writing custom software to communicate and …


An Integrated Resource Plan For Arizona Public Service Electric (Aps), Irene Boghdadi, Randy Chiu May 2020

An Integrated Resource Plan For Arizona Public Service Electric (Aps), Irene Boghdadi, Randy Chiu

Master's Projects and Capstones

Our Masters Capstone Project is an Integrated Resource Plan (IRP) for Arizona’s largest electric utility, Arizona Public Service Electric (APS).

An IRP is developed by utilities to identify the optimal combination of demand- and supply-side resources needed to reliably meet forecasted demand for energy and capacity, including a planning reserve margin, over a future period.

In addition to APS’s obligation to serve the growing load in Arizona while minimizing costs, it is required by the state to adhere to the Renewable Energy Standard (RES) policy of 15 percent retail sales from renewable energy resources by 2025.

The analysis described in …


Application Of Optimal Switching Using Adaptive Dynamic Programming In Power Electronics, Ataollah Gogani Khiabani May 2020

Application Of Optimal Switching Using Adaptive Dynamic Programming In Power Electronics, Ataollah Gogani Khiabani

Mechanical Engineering Research Theses and Dissertations

In this dissertation, optimal switching in switched systems using adaptive dynamic programming (ADP) is presented. Two applications in power electronics, namely single-phase inverter control and permanent magnet synchronous motor (PMSM) control are studied using ADP. In both applications, the objective of the control problem is to design an optimal switching controller, which is also relatively robust to parameter uncertainties and disturbances in the system. An inverter is used to convert the direct current (DC) voltage to an alternating current (AC) voltage. The control scheme of the single-phase inverter uses a single function approximator, called critic, to evaluate the optimal cost …


Control And Locomotion Of Inertially And Magnetically Actuated Multi-Scale Robotic Systems, Ehab Al Khatib May 2020

Control And Locomotion Of Inertially And Magnetically Actuated Multi-Scale Robotic Systems, Ehab Al Khatib

Mechanical Engineering Research Theses and Dissertations

In this research, two actuation systems were introduced, inertial and magnetic actuation. In the inertial actuation, the robot used the transfer of momentum to navigate, and this momentum could be generated by spinning masses and wheels. Recent studies in our System Laboratory proved that a wide range of inertially actuated locomotion systems could be generated. This can be achieved by using a family tree approach, starting from a very simple system, and progressively evolving it to more complex ones. The motion diversity of these robots inspired us to extend their locomotion from a macro scale to millimeter and micro scales. …


Development And Test Of High Temperature Surface Acoustic Wave Gas Sensors, Armando E. Ayes Moncada May 2020

Development And Test Of High Temperature Surface Acoustic Wave Gas Sensors, Armando E. Ayes Moncada

Electronic Theses and Dissertations

The demand for sensors in hostile environments, such as power plant environments, exhaust systems and high-temperature metallurgy environments, has risen over the past decades in a continuous attempt to increase process control, improve energy and process efficiency in production, reduce operational and maintenance costs, increase safety, and perform condition-based maintenance in equipment and structures operating in high-temperature, harsh-environment conditions. The increased reliability, improved performance, and development of new sensors and networks with a multitude of components, especially wireless networks, are the target for operation in harsh environments. Gas sensors, in particular hydrogen gas sensors, operating above 200°C are required in …


3-D Silk Fibroin Porous Particles Created By The Ouzo Effect For Biomedical Applications, Ashley Nicole Lamb May 2020

3-D Silk Fibroin Porous Particles Created By The Ouzo Effect For Biomedical Applications, Ashley Nicole Lamb

UNLV Theses, Dissertations, Professional Papers, and Capstones

Due to its high biocompatibility and biodegradability, silk fibroin – produced from

Bombyx mori (B. mori) cocoons – has been at the forefront of research for many

biomedical application formats: hydrogels, films, microspheres, and porous

sponges/scaffolding, to name a few. For drug delivery, in particular, porous particles are

desirable for their large surface area, uniform and tunable pore structure, and high

porosity. This thesis focuses on the fabrication of porous particles from silk fibroin by the

very interesting Ouzo effect. The Ouzo effect, so named because of the Greek

beverage ouzo, describes the phenomenon of an ethanol + anethole oil …


3d Parametric Hand To Improve Prosthetic Hand Functionality, Maria C. Gerardi May 2020

3d Parametric Hand To Improve Prosthetic Hand Functionality, Maria C. Gerardi

UNLV Theses, Dissertations, Professional Papers, and Capstones

The use of prosthetics can significantly enhance an individual’s standard of living, not only offering functional advantages but psychological advantages as well. Unfortunately for children with upper limb reduction, options are limited and rejection rates are high due to a multitude of reasons including discomfort and poor functionality. This study proposes a new parametric 3D design model (Parametric Hand) with an adjustable thumb that can be easily manipulated to the uniqueness of an individual. The Parametric Hand was evaluated, both qualitatively and quantitatively, against the Flexy-Hand 2, a commonly used prosthetic hand. The results showed insignificant differences in all testing …


Investigation Of Navigation Systems For Size, Cost, And Mass Constrained Satellites, Omar Awad Apr 2020

Investigation Of Navigation Systems For Size, Cost, And Mass Constrained Satellites, Omar Awad

USF Tampa Graduate Theses and Dissertations

The feasibility of using radically inexpensive micro-electromechanical system (MEMS) technology for navigation of a nanosatellite is investigated with a focus on attitude estimation. Typically, larger satellites are equipped with star cameras, sun sensors, or Earth horizon sensors for attitude estimation. These sensors can provide very accurate attitude measurements. A nanosatellite is highly size, power, and cost constrained and cannot readily accommodate these sensors. Our mission is to design, build, and operate a radically inexpensive nanosatellite system. While there is no consensus on what constitutes a "radically inexpensive" satellite, our goal is a maximum cost of $10,000 per unit. This precludes …


Characterization Of Reactive Ion Etch Chemistries Using Direct Write Lithography, Dylan T. Martin-Abood Mar 2020

Characterization Of Reactive Ion Etch Chemistries Using Direct Write Lithography, Dylan T. Martin-Abood

Theses and Dissertations

The DoD requires a variety of COTS and number of custom microelectronics to provide important functionality to critical military systems. Photolithography and DRIE are two techniques commonly used in the development of deep anisotropic features for the fabrication and modification of microelectronics and MEMS. However, standard photolithography techniques are ineffective for unique substrate geometries and DRIE processes require a chemical passivation step only applicable to Si substrates. This work confirmed the capability of RIE using DWL to perform deep, highly selective, anisotropic etching on elevated, non-circular substrates.


Development Of An Eco Approach And Departure Application To Improve Energy Consumption Of A Plug-In Hybrid Vehicle In Charge Depleting Mode, Brandon Narodzonek Jan 2020

Development Of An Eco Approach And Departure Application To Improve Energy Consumption Of A Plug-In Hybrid Vehicle In Charge Depleting Mode, Brandon Narodzonek

Dissertations, Master's Theses and Master's Reports

A recent study at Michigan Technological University as part of the NEXTCAR DOE APRA-E Project was conducted to determine the potential energy savings of a plug-in hybrid electric vehicle (PHEV) equipped with various Connected and Automated Vehicle (CAV) Technologies. One aspect of this study focused on the development of an Eco Approach and Departure (Eco AnD) Application that would further reduce the energy consumed around a signalized intersection.

Many modern intersections are equipped with traffic signals that can broadcast Basic Safety (BSM), MAP, and Signal Phase and Timing (SPaT) message sets that contain intersection ID, location, current phase, and cyclic …


Dual-Axis Solar Tracker, Bryan Kennedy Jan 2020

Dual-Axis Solar Tracker, Bryan Kennedy

All Undergraduate Projects

Renewable energies, and fuels that are not fossil fuel-based, are one of the prolific topics of debate in modern society. With climate change now becoming a primary focus for scientists and innovators of today, one of the areas for the largest amount of potential and growth is that of the capturing and utilization of Solar Energy. This method involves using a mechanical system to track the progression of the sun as it traverses the sky throughout the day. A dual-axis solar tracker such as the one designed and built for this project, can follow the sun both azimuthally and in …


Accurate Replication Of An Ear Pinnae Geometry For Use In Acoustic Testing Of Spatial Cues And Sound Localization, Alejandra Belmont Jan 2020

Accurate Replication Of An Ear Pinnae Geometry For Use In Acoustic Testing Of Spatial Cues And Sound Localization, Alejandra Belmont

Open Access Theses & Dissertations

Additive manufacturing (AM) enables freedom of design as well as fabrication of complex objects such as the human hear. In medical modeling there is a need for patient-specific customizable parts. The outer human ear consists of these main parts: the pinna, which naturally filters sound, and the ear canal, which is the point at which sound enters before being moved up to the tympanic membrane, otherwise known as the eardrum. In an attempt to accurately replicate ear models, the use of scanning and reverse engineering methods was used. A comparison of 3D laser scanning systems was performed to determine their …


Sensor Fusion And Non-Linear Mpc Controller Development Studies For Intelligent Autonomous Vehicular Systems, Ahammad Basha Dudekula Jan 2020

Sensor Fusion And Non-Linear Mpc Controller Development Studies For Intelligent Autonomous Vehicular Systems, Ahammad Basha Dudekula

Dissertations, Master's Theses and Master's Reports

The demand for safety and fuel efficiency on ground vehicles and advancement in embedded systems created the opportunity to develop Autonomous controller. The present thesis work is three fold and it encompasses all elements that are required to prototype the autonomous intelligent system including simulation, state handling and real time implementation. The Autonomous vehicle operation is mainly dependent upon accurate state estimation and thus a major concern of implementing the autonomous navigation is obtaining robust and accurate data from sensors. This is especially true, in case of Inertial Measurement Unit (IMU) sensor data. The IMU consists of a 3-axis gyro, …


Identification Of Heat Release Shapes And Combustion Control Of An Ltc Engine, Radhika Sitaraman Jan 2020

Identification Of Heat Release Shapes And Combustion Control Of An Ltc Engine, Radhika Sitaraman

Dissertations, Master's Theses and Master's Reports

Low Temperature Combustion (LTC) regimes have gained attention in internal combustion engines since they deliver low nitrogen oxides (NOx) and soot emissions with higher thermal efficiency and better combustion efficiency, compared to conventional combustion regimes. However, the operating region of these high-efficiency combustion regimes is limited as it is prone to knocking and high in-cylinder pressure rise rate outside the engine safe zone. By allowing multi-regime operation, high-efficiency region of the engine is extended. To control these complex engines, understanding and identification of heat release rate shapes is essential. Experimental data collected from a 2 liter 4 cylinder LTC engine …


Rc Mini Baja Car - Suspension And Chassis, Collin Mckenzie Jan 2020

Rc Mini Baja Car - Suspension And Chassis, Collin Mckenzie

All Undergraduate Projects

Two students have developed a unique design of the RC Baja Car to optimize functionality and performance. A Baja car is a remote controlled 1/10 scale car that is used for recreation or competition, usually meant for competing in the ASME Baja car competition versus various schools. The competition focuses on the best time achieved in different courses that utilize speed, turns, and jumps. The objective for the project was to create a unique suspension from previous individual’s projects by creating a four-link suspension in which allows more travel in the suspension of the car and maintains functionality with the …


A Study Of Model-Based Control Strategy For A Gasoline Turbocharged Direct Injection Spark Ignited Engine, Xin Wang Jan 2020

A Study Of Model-Based Control Strategy For A Gasoline Turbocharged Direct Injection Spark Ignited Engine, Xin Wang

Dissertations, Master's Theses and Master's Reports

To meet increasingly stringent fuel economy and emissions legislation, more advanced technologies have been added to spark-ignition (SI) engines, thus exponentially increase the complexity and calibration work of traditional map-based engine control. To achieve better engine performance without introducing significant calibration efforts and make the developed control system easily adapt to future engines upgrades and designs, this research proposes a model-based optimal control system for cycle-by-cycle Gasoline Turbocharged Direct Injection (GTDI) SI engine control, which aims to deliver the requested torque output and operate the engine to achieve the best achievable fuel economy and minimum emission under wide range of …


Development Of An Anatomically And Electrically Conductive Brain Phantom For Transcranial Magnetic Stimulation, Hamzah A. Magsood Jan 2020

Development Of An Anatomically And Electrically Conductive Brain Phantom For Transcranial Magnetic Stimulation, Hamzah A. Magsood

Theses and Dissertations

Transcranial Magnetic Stimulation (TMS) is a non-invasive technique for diagnostics, prognostic, and treatments of various neurological diseases. However, the lack of anatomically realistic brain phantoms has made the experimental verification of stimulation strength in the form of induced electric fields/voltages in the brain tissues an impediment to developing new TMS coils, stimulators, and treatment protocols. There are significant technological, safety, and ethical limitations to test the potential TMS treatment procedures or develop enhancements and refine them on humans or animals. This work aims to bridge the gap by introducing and developing an innovative manufacturing and fabrications process to produce a …


Tabletop Mechanical Tester, Jamie Dombroski, Brian English, Richard Leffler, Andrew Shirk Jan 2020

Tabletop Mechanical Tester, Jamie Dombroski, Brian English, Richard Leffler, Andrew Shirk

Williams Honors College, Honors Research Projects

The need for hands-on and face-to-face experiences in the engineering classroom is very great. The equations, principles, and concepts can all be learned, but without the visual and tactile application, these don’t always sink in or become concrete. A small-scale tensile test machine was designed, sourced, manufactured, and tested for the purpose of being applied in classroom settings to provide this experience to engineering students. Extensive research was performed concerning tensile machines on the market, the essential elements of which are the load cell, grips, crosshead, extensometer, motor, and frame. The raw materials for the frame were purchased and drawings …


Ultrasonic-Based Condition Assessment Of Wooden Utility Poles, Yishi Lee Jan 2020

Ultrasonic-Based Condition Assessment Of Wooden Utility Poles, Yishi Lee

Electronic Theses and Dissertations

More than 300 million utility poles shoulder the utility grid in the United States. However, the ineffectiveness of the current inspection process causes roughly a third of utility poles removed from the service deemed suitable for reuse. Due to the utterly essential role of the power infrastructure, budget shrinkage, and the structural degradation of the modern distribution grid, this Ph.D. dissertation addresses the challenges by proposing a physics-based signal analysis method with a jointly developed ultrasonic UB1000 system c to enhance the objectivity in ultrasonic-based nondestructive evaluation (NDE). The proposed methodology has been deployed commercially in the field and featured …


Implementation Of Radial Basis Function Artificial Neural Network Into An Adaptive Equivalent Consumption Minimization Strategy For Optimized Control Of A Hybrid Electric Vehicle, Thomas P. Harris Jan 2020

Implementation Of Radial Basis Function Artificial Neural Network Into An Adaptive Equivalent Consumption Minimization Strategy For Optimized Control Of A Hybrid Electric Vehicle, Thomas P. Harris

Graduate Theses, Dissertations, and Problem Reports

Continued increases in the emission of greenhouse gases by passenger vehicles has accelerated the production of hybrid electric vehicles. With this increase in production, there has been a parallel demand for continuously improving strategies of hybrid electric vehicle control. The goal of an ideal control strategy is to maximize fuel economy while minimizing emissions. The design and implementation of an optimized control strategy is a complex challenge. Methods exist by which the globally optimal control strategy may be found. However, these methods are not applicable in real-world driving applications since these methods require a priori knowledge of the upcoming drive …


Real-Time Predictive Control Of Connected Vehicle Powertrains For Improved Energy Efficiency, Joseph Oncken Jan 2020

Real-Time Predictive Control Of Connected Vehicle Powertrains For Improved Energy Efficiency, Joseph Oncken

Dissertations, Master's Theses and Master's Reports

The continued push for the reduction of energy consumption across the automotive vehicle fleet has led to widespread adoption of hybrid and plug-in hybrid electric vehicles (PHEV) by auto manufacturers. In addition, connected and automated vehicle (CAV) technologies have seen rapid development in recent years and bring with them the potential to significantly impact vehicle energy consumption. This dissertation studies predictive control methods for PHEV powertrains that are enabled by CAV technologies with the goal of reducing vehicle energy consumption.

First, a real-time predictive powertrain controller for PHEV energy management is developed. This controller utilizes predictions of future vehicle velocity …


Filtered-Dynamic-Inversion Control For Unknown Minimum-Phase Systems With Unknown Relative Degree, Sumit Suryakant Kamat Jan 2020

Filtered-Dynamic-Inversion Control For Unknown Minimum-Phase Systems With Unknown Relative Degree, Sumit Suryakant Kamat

Theses and Dissertations--Mechanical Engineering

We present filtered-dynamic-inversion (FDI) control for unknown linear time-invariant systems that are multi-input multi-output and minimum phase with unknown-but-bounded relative degree. This FDI controller requires limited model information, specifically, knowledge of an upper bound on the relative degree and knowledge of the first nonzero Markov parameter. The FDI controller is a single-parameter high-parameter-stabilizing controller that is robust to uncertainty in the relative degree. We characterize the stability of the closed-loop system. We present numerical examples, where the FDI controller is implemented in feedback with mathematical and physical systems. The numerical examples demonstrate that the FDI controller for unknown relative degree …