Electro-Mechanical Systems Commons^™

Design, Fabrication And Characterization Of Zero Power Sensor/Harvester For Smart Grid Applications, Zeynel Guler

Mechanical Engineering ETDs

This study presents a flexible sensor/harvester device to be used in both electromagnetic sensing and energy harvesting applications for smart grids. When a current passes through a wire, the sensor detects the magnetic field created by that current. The sensor magnet interacts with the wire magnetic field resulting in a transfer of energy through the piezoelectric cantilever. Piezoelectric, conductive, magnetic, and magnetostrictive composite thin films were prepared to fabricate this device.

Initially, the magnet of the cantilever was optimized considering its shape, thickness, length, taper angle etc. via both simulations and experiments. Peak to peak voltage versus cantilever position graph …

Silver Sintering Reliability And Its Enhancement For Use In High-Density Power Modules, Alicia Medina Garcia

Graduate Theses and Dissertations

This master's thesis is dedicated to enhancing the reliability of silver sinter die attachments, a pivotal component within the dynamic realm of power electronics. The study is meticulously organized into four distinct chapters, each contributing to a comprehensive understanding of silver sinter die attachment reliability and its implications for contemporary electronic packaging. In Chapter 1, an introduction is provided to the significance of silver sinter die attachment in the context of power electronics, underlining the imperatives associated with miniaturization, weight reduction, and heightened efficiency. The compelling need to investigate die attachment properties, particularly in high-temperature and high-power-density environments, is emphasized. …

Cnc Retrofits, Fabian Samano, Murat Askin, Daniel Lonczak, Zane Campise

Mechanical Engineering

The Boxford CNC Lathe is a machine used for educational purposes. The goal of the CNC Retrofits project is to improve the Boxford MT2’s performance and functionality to enable Mr. Lonczak to manufacture customized ballpoint pens. Within this Final Design Review (FDR) document, we present design updates since the CDR and implementation/assembly techniques. This work culminates in a solution to Mr. Lonczak’s needs which is analyzed in three subsystems: main control, spindle position tracking, and user interface. Within this report, we show the results of each subsystem’s verification process. These results prove that the design concept was met by describing …

Thermal Resistance Characterization Of High-Voltage Sic Power Module, Landon Lemmons

Mechanical Engineering Undergraduate Honors Theses

Researchers within the University of Arkansas Electrical Engineering Research Department have embarked on a project aimed at enhancing the thermal performance of high-voltage power modules. To aid in the progress of this project, the design, and development of a thermal tester device are needed. The primary objective of this device is to determine the various thermal properties of high-voltage power modules that the electrical engineering department has developed. Additionally, the project aims to facilitate electrical loading tests on power modules and provide researchers with the means to calibrate the power module in terms of thermal load. This project also possesses …

Advanced Jet Impingement Cooling For Power Electronics, Reece Whitt

Graduate Theses and Dissertations

Convective heat transfer by jet impingement cooling offers a suitable solution for high heat flux applications. Compared to techniques that rely on bulk conduction in series with convection, direct liquid impingement reduces the thermal resistance between power device hot spots and the coolant. Using additive manufacturing processes, location specific jets can be integrated into high voltage power electronics systems. Custom manifolds can be designed to reduce pressure drop, while simultaneously fine-tuning the thermal management efficiency. Although capable of highly efficient cooling, static impingement devices must be designed for the worst-case cooling requirements for a transient power profile, possibly resulting in …

Accelerated Testing Of Solder Spheres Under Combined Temperature, Current, And Shear Stresses To Estimate Reliability, Collin Ruby

Graduate Theses and Dissertations

With the densification of power electronics in the pursuit of decreased size and weight and increased efficiency, the need to investigate the properties of solder in packages with higher working temperatures and power densities is becoming apparent. Many research groups have conducted accelerated testing using methods such as thermal aging, shear or tensile stress tests, or electromigration tests, but relatively little research exists that considers the impact of several stresses in a combined study. This work aims to produce a novel method for estimating the lifetime of SAC305 solder joints under a combined stress scenario, which more accurately depicts the …

Tagalong Trail, Sean Wahl, Jason Davis, Quinlan Stephens, Ryan Johnson, Vinh Vo

Mechanical Engineering

The Cal Poly mechanical engineering team working on the Path of Lights and Sounds for the Girl Scouts of California’s Central Coast has now completed their project. In the last quarter of their project, they were able to finalize their tile’s structural design while iterating through several electronics board designs. Through this iteration, they were able to create a final electronics board and designed a water-resistant enclosure to house the board. A new team member was added, allowing them to manufacture 28 tile structures and 30 electronics assemblies over the course of two and a half weeks. This proved to …

Integrated Actuator, David Hefter, Mathew Smith, Amanda Westmoreland, Akanksha Maddi

Mechanical Engineering

This Final Design Review document outlines the senior project design that we, a team of four mechanical engineering students at California Polytechnic State University, are developing for Charlie Refvem, a lecturer in the mechanical engineering department. The final design has undergone significant modifications since the Critical Design Review, such as a redesigned vertical shaft, material changes, and the incorporation of belt tensioners. These redesigns are thoroughly discussed in the context of testing and assembly error resolution.

The document outlines the detailed steps for the production and testing of the design verification prototype. This includes the procurement and manufacturing of components, …

Gpu Based Monte Carlo Estimation Of Eddy Current Losses In Electromagnetic Coil-Core System, Adwaith Ravichandran

Theses and Dissertations

A novel parallelizable probabilistic approach to model eddy currents in AC electromagnets is presented in this research. Consequently, power loss associated with the formation of these eddy currents is estimated and validated using experimental data. Furthermore, predicting the effect of ferromagnetic alternating field enhancement on power loss in the source excitation winding has been an active area of research. Unlike a stationary field, an alternating sinusoidal field diffuses partially into the ferromagnetic material leading to a predictably sub-optimal field enhancement. To model these physics, finite element techniques employ nonlinear iterative solvers which are time consuming. A novel method is developed …

Investigating Mems Devices In Flow Conditions Relevant To Flow-Through Systems., Mohammad Shafquatul Islam

Electronic Theses and Dissertations

Advancements in microscale actuating technologies has substantially expanded the possibilities of interacting with the surrounding environment. Microstructures that deflect in response to mechanical forces are one of the largest application areas of microelectromechanical systems (MEMS). MEMS devices, functioning as sensors, actuators, and support structures, find applications in inertial sensors, pressure sensors, chemical sensors, and robotics, among others. Driven by the critical role of catalytic membrane reactors, this dissertation aims to evaluate enzyme activity on polymeric membranes and explore how fabrication methods from the field of Electrical and Computer Engineering (ECE) can incorporate sensing and actuation into these porous surfaces. Toward …

Improving Hexapod Platform Pose Accuracy - A Photogrammetry-Based Approach, Sourabh Karmakar

All Dissertations

The aim of this research is to make a newly constructed Stewart-Gough Platform-based test frame Tiger 66.1 operational by developing control software and estimating the error in its pose accuracy. The accuracy of the platform is affected by one source or multiple sources. The typical error sources are kinematic and structural, some of them originate from manufacturing imperfections, assembly deviations, elastic deformations, thermal deformations, and joint clearances which change the expected kinematic behavior of the manipulator. Also, some non-mechanical errors like transmission error, sensor accuracy, algorithm error, and truncation error in calculation contribute significantly in some cases. Using pose deviations …

Damage Detection With An Integrated Smart Composite Using A Magnetostriction-Based Nondestructive Evaluation Method: Integrating Machine Learning For Prediction, Christopher Nelon

All Dissertations

The development of composite materials for structural components necessitates methods for evaluating and characterizing their damage states after encountering loading conditions. Laminates fabricated from carbon fiber reinforced polymers (CFRPs) are lightweight alternatives to metallic plates; thus, their usage has increased in performance industries such as aerospace and automotive. Additive manufacturing (AM) has experienced a similar growth as composite material inclusion because of its advantages over traditional manufacturing methods. Fabrication with composite laminates and additive manufacturing, specifically fused filament fabrication (fused deposition modeling), requires material to be placed layer-by-layer. If adjacent plies/layers lose adhesion during fabrication or operational usage, the strength …

Examining The Efficacy Of Using Irt As An Nde Method For Cfrp And Ztcfrp Composites, William Wyatt Taylor

Graduate Theses and Dissertations (2019 - present)

A film adhesive is commonly used to form the bond-line between composite parts. The bond-line's quality and performance can be affected by defects such as voids, impurities, and agglomerations. Identifying these defects is possible with non-destructive evaluation testing (NDE). In this thesis, the joule-heating effect (JH) through carbon nanofiber (CNF) and carbon nanotube (CNT) modified film adhesive bonded to control carbon fiber reinforced polymer (CCFRP) was used along with infrared thermography testing (IRT) for bond-line defect inspection as a preliminary study. Due to the difference in the electrical conductivity between the modified epoxy and the defect, JH can cause a …

Controlled Radiation Capsule For Precision And Rapid Cancer Treatment, Hoseon Lee, Zsolt Kollar, Bailey R. White, Junia Nguyen, David Roque, Sowjanya Palagani

Symposium of Student Scholars

This research aims to transform cancer treatment through the optimization of brachytherapy, with a focus on reducing treatment duration, setup complexities, and financial burdens, all while emphasizing patient safety. Patients living at a distance from radiation clinics, particularly those undergoing extended Low Dose Radiation brachytherapy, often struggle with the formidable financial challenges associated with securing nearby accommodations. In response to these issues, the research introduces a radiation capsule designed to condense the conventional six-month treatment period to approximately just one week, thereby significantly reducing the duration of required accommodations. This capsule is especially relevant considering the construction cost of $40 …

Impact Of Silicon Ion Irradiation On Aluminum Nitride-Transduced Microelectromechanical Resonators, David D. Lynes, Joshua Young, Eric Lang, Hengky Chandrahalim

Faculty Publications

Microelectromechanical systems (MEMS) resonators use is widespread, from electronic filters and oscillators to physical sensors such as accelerometers and gyroscopes. These devices' ubiquity, small size, and low power consumption make them ideal for use in systems such as CubeSats, micro aerial vehicles, autonomous underwater vehicles, and micro-robots operating in radiation environments. Radiation's interaction with materials manifests as atomic displacement and ionization, resulting in mechanical and electronic property changes, photocurrents, and charge buildup. This study examines silicon (Si) ion irradiation's interaction with piezoelectrically transduced MEMS resonators. Furthermore, the effect of adding a dielectric silicon oxide (SiO₂) thin film is …

Robotic Origami Worm, Carter Josef, Michael Freeman, Mohammad Hasan

College of Engineering Summer Undergraduate Research Program

Soft robotics can solve many unique engineering problems. The ancient art of origami has inspired design for a new breed of robots. In this research, a novel fold design was created which has high linear stiffness, high bending stiffness, and the ability to deform omnidirectionally in order to turn. The robot is operated using a DC motor to expand and contract and electromagnets to control friction. The robot moves very quickly compared with many other origami robots in the literature. Other interesting ways to control friction were explored including expansion mechanisms. An origami design was created and tested that expands …

Explorations In Monocular Distance And Ranging (Modar) Techniques For Real-World Applications, Devon Vail

Doctoral Dissertations and Master's Theses

In this work, an initial prototype of a monocular camera system capable of retrieving depth-from-focus using a liquid focus-tunable lens is constructed out of hobby-grade photography equipment. This concept has been explored previously in laboratory settings using specialized equipment; this work seeks to determine the feasibility of retrieving depth-from-focus using commercially available components. To achieve this, an iterative exploration of existing techniques was performed to verify their utility in the final ensemble of processes to retrieve depth from 2D images. Initially, blurry images were simulated by applying Gaussian blur to test images to verify the functionality of a Laplacian of …

Wire Deflection Investigation During Wedm Of Aisi 304 Stainless Steel: An Experimental And Numerical Study, Sara A. El-Bahloul, Mohamed G. Elkhateeb

Mansoura Engineering Journal

Wire electrical discharge machining (WEDM) is a specific form of electrical discharge machining that employs a small diameter wire electrode to cut a narrow kerf in the workpiece. Since the wire deflection has a negative effect on the performed cutting, this research seeks to study the resultant wire deflection during WEDM of AISI 304 stainless steel. This study is performed with the help of three types of modeling; namely, mathematical modeling, experimental modeling, and thermo-mechanical finite element modeling. The mathematical modeling is performed to analyze the stresses and the wire lag, while the experimental modeling is achieved to observe the …

A Multi-Aerial Vehicle Platform For Testing Collaborative Mobility Formation Controllers, Matthew Snellgrove

LSU Master's Theses

Multi-agent systems have potential applications in a multitude of fields due to their ability to perform complex tasks with a high degree of robustness. Decentralized systems are multi-agent systems where sensing, control, and communication responsibilities are distributed amongst the agents giving this scheme a particularly high potential for robustness, adaptability, and complexity; however, this comes with its own list of challenges. Formation control is a topic in multi-agent systems that aims to have the agents moving as a virtual rigid body through space. In the literature, there have been successful implementation of formation control algorithms on robot agents in both …

A Robust Model Reduction For The Optimal Boundary Feedback Stabilization Of Magnetizable Piezoelectric Beams, Md Rafi As Sadeq Ibn Emran

Masters Theses & Specialist Projects

The one-dimensional Partial Differential Equation (PDE) model of the wave equation, which describes wave dynamics of a wide-range of controlled mechanical systems, with a state feedback controller at its boundary is known to have exponentially stable solutions. Moreover, it is also reported that the several model reductions of the wave equation by the standard Finite Differences and Finite Elements approximations suffer from the lack of exponential stability (and exact observability without a state feedback controller) uniformly as the discretization parameter tends to zero. This is due to the loss of a uniform gap among the high-frequency eigenvalues as the discretization …

Miniature, Submersible Electromagnetic Pumps Of Molten Lead And Sodium For Gen-Iv Nuclear Reactors Development, Ragai M. Altamimi

Nuclear Engineering ETDs

Heavy metals and alkali Liquid Metals are suitable coolants for Generation IV terrestrial nuclear reactors for operating at elevated temperatures for achieving plant thermal efficiency more than 40% and the thermochemical generation of hydrogen fuel. In addition, the low vapor pressure of these liquids eliminates the need for a pressure vessel and instead operates slightly below ambient pressure. A primary issue with the uses of these coolants is their compatibility with nuclear fuel, cladding and core structure materials at elevated temperatures more than 500oC. Therefore, in pile and out-of-pile test loops have been constructed or being considered for quantifying the …

Northrop Grumman Collaboration Project, Nikkia Psomas-Sheridan, Santiago Robles, Ben Elkayam, Benjamin Ulfhake

Mechanical Engineering

The Northrop Grumman Collaboration Project (NGCP) is a collaborative club project sponsored by Northrop Grumman for the students of Cal Poly San Luis Obispo (CPSLO) and Cal Poly Pomona (CPP) to create a fleet of vehicles to aid in the simulated rescue of stranded hiker. The CPSLO club is responsible for delivering an autonomous flight vehicle that can suppress a fire and retrieve a payload. Mechanical Design Team of the CPSLO team was responsible for the design of the frame, electronics housing, and payload and fire suppression systems.

Aeroponic System Optimization For Butterhead Lettuce Growth And Future Sustainability Using Flow Blurring Atomization, Taylor J. Johnson

Doctoral Dissertations and Master's Theses

The global population has grown by 6 billion people over the last century and is trending toward 9.7 billion people by the year 2050. Agriculture accounts for 70% of global fresh water usage. Technology must be developed to accommodate the increase of food production demanded by the growing global population and the subsequent increase in water usage. Aeroponic technology is a water-efficient vertical farming technology that can reduce water usage by 90% by suspending plant roots in air within a controlled chamber and supplying atomized droplets of a water-nutrient solution directly to the roots.

This study simultaneously tests six droplet …

Animatronic Monarch Butterfly: Mechanical System, Janine Rae Moreno, Enrico Cruz, Alexia Murphy, Lakshmanan Muthukaruppan

Mechanical Engineering

This report describes the design, manufacturing, and design verification of an interactive animatronic monarch butterfly created by a team of mechanical and computer engineering students for the Girl Scouts of California's Central Coast. The purpose of the project is to engage Girl Scouts in learning about monarch butterflies and provide hands-on experience in robotics and STEM. The report covers design changes, manufacturing processes, and assembly of various components, including the butterfly body, wings, legs, and electronic housing. The software and electronics used in the project are also briefly discussed, as the computer engineering team was responsible for the software and …

Power Thyristor Controller For Speed Control Of Dc Motor, Alejandra Zapata, Morgan Erich Boehme, Abdullah Mohammed Awidah, Payton Robert Chalstrom

Electrical Engineering

In this work, a Power Thyristor Controller for Speed Control of DC Motor has been developed with the purpose of replacing an existing simulation experiment, aiming to effectively implement the principle of learning by doing. The primary objective of the experiment setup is to illustrate the fundamental principles and operational mechanisms underlying the firing angle and controlled bridge rectifier. The new experiment is taking advantage of the existing FCRO4100 Single Phase Firing Board that was donated to the University by ENERPRO. The pre-programmed microcontroller is connected to the thyristor bridge rectifier that’s powered by 24VAC. Additionally, a DC motor will …

Weed Robot, Kaela Stern, Lewis Kanagy, Claire Franz, Carlos Rodriguez Orozco, Jackie Chen, Sachi Hiji, Ayush Kakkanat, William Ta

Mechanical Engineering

Team Weed Scouts has completed our work on a weed-cutting robot for the Girl Scouts of California’s Central Coast. The final robot build provides a solid foundation that can be built and improved upon by future teams. We have completed the robot base and structure, including the chassis, drivetrain, and robot shell. We also completed manufacturing a weed storage bin and canvas cover for the robot. Additionally, we have built a weed scooper, the mechanism that cuts weeds and transports them into a storage compartment. The electronics and programming for remote control of the robot are also implemented. After some …

In-Situ Mechanical Tester, Andrrew Murach, Gustavo Marquez, Kosimo Tonn, Jake Vormbaum

Mechanical Engineering

Over the course of the 2022-23 Cal Poly SLO school year, a small tensile tester device was developed specifically for Dr. Long Wang to test thin film materials under a microscope and generate accurate force versus displacement graphs. A tensile tester was manufactured using purchased and machined components, electronics were consolidated in a separate box and connected, and a program and user interface were written to control the motion, provide custom inputs, and organize useful data for the researcher. Tests were conducted to compare the performance of the device to universal tensile testers available in the Composites lab. The device …

Baja Sae Semi-Active Suspension, Cameron Paul Jones, Ethan Jacobi Mikel, Joshua Macguire Wright, Aditya Garg

Mechanical Engineering

This document outlines the design and justification for the final design of the Baja SAE Semi-Active Suspension Senior Project. The goal of the project was to build a base valve that can adjust suspension damping rates on the fly. This document details the ideation, design, manufacturing, design verification results, and detailed drawing package for the project. Additionally, this document includes information regarding the pressure drop calculator, O-ring calculations, and CAD. The manufacturing processes used to create the valve and the testing and evaluation of the valve are included as well. Finally, the methods that were used to manage this project …

Sky Survey Radio Telescope, Jack E. Mcguigan

Electrical Engineering

This document outlines the design of a radio telescope designed to perform hydrogen line sky surveys. The telescope produces radio images mapping the intensity and relative velocities of hydrogen concentrations to their sky coordinates. Over the course of a day, the telescope images the regions of space visible to it, allowing sky survey imagery to be updated daily. Sky survey images are comprised of an array of pixels corresponding to specific sky coordinates. Each 8-bit RGB pixel contains information on the concentrations of hydrogen in the brightness and relative velocity in the color. Radio images mapping the concentrations and velocities …

Rapid Composter, Shannon Shinozaki, Avin Atencio, Jonathan Fraser, Lukas Kolbl, Russell Occhipinti

Mechanical Engineering

This project was created with the intent of automatically composting equine bio waste to be reused as plant fertilizer. The system consists of four subsystems: power generation and storage, automatic controls, aeration, and structure. Each subsystem may be manufactured independently, then put together. This system will not have access to power outlets, so it was designed to be solar-powered.