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Articles 1 - 30 of 48
Full-Text Articles in Engineering
Affordable Bioprint Head-Adapter For 3d Printers, Andrew Ceralde, Dominic Drake, Noah Engles, Mohammad Alwan, Nevada Perry
Affordable Bioprint Head-Adapter For 3d Printers, Andrew Ceralde, Dominic Drake, Noah Engles, Mohammad Alwan, Nevada Perry
Honors Capstones
Introduction: Addressing the need for affordable and accessible bioprinting technology, the Northern Illinois University bioprinting research and design project aims to democratize the field by developing an open source bioprint head. The initiative targets the prohibitive cost of commercial bioprinters by proposing an optimal design that can be integrated with widely available 3D printers, like the Creality Ender-3. This approach seeks to enable the widespread adoption of bioprinting technology, particularly for applications in tissue engineering and regenerative medicine.
Methods: Leveraging SolidWorks for design, the project employs a methodology that combines a precision extrusion system with thermal and UV crosslinking capabilities. …
Improving The Power Efficiency Of Woodward’S High-Power Inverter (Hpi) Using Algorithmic Part Selection., Jaron Holder, Ali Al Gazwi, John Childers, Jose Soublett
Improving The Power Efficiency Of Woodward’S High-Power Inverter (Hpi) Using Algorithmic Part Selection., Jaron Holder, Ali Al Gazwi, John Childers, Jose Soublett
Honors Capstones
Woodward Inc. is a secondary aerospace manufacturer based in the USA that specializes in aircraft power and control systems. This senior design project was concerned with a power systems platform currently in development by Woodward, the High-Power Inverter (HPI) system. In this report, the senior design group from Northern Illinois University (NIU) demonstrated the creation of an algorithmic part selection process to choose more power-efficient electrical components, the prototyping using MATLAB Simulink, and the practical testing that showed an increase of 7% in the power efficiency of the HPI system.
Spectrophotometric Device For Early Malaria Detection, Adrian Wasylewski, Christopher Faber, Victor Lin
Spectrophotometric Device For Early Malaria Detection, Adrian Wasylewski, Christopher Faber, Victor Lin
Honors Thesis
Malaria remains a significant global health challenge, with millions of cases reported annually, particularly in resource-limited regions. Timely and accurate diagnosis is crucial for effective treatment and disease management. Unfortunately, there are still significant challenges in existing testing procedures, which are often expensive, inaccurate, or impractical for mass testing. While spectrophotometry has been proposed as a detection tool for other tropical diseases such as dengue fever, no prototype has been made for any disease, including malaria. This report addresses this gap by presenting a spectrophotometric-based malaria detection tool that achieves high sensitivity at a low cost. The inclusion of a …
A Tessellation Of Engineers, Grace Jenkins Welsh
A Tessellation Of Engineers, Grace Jenkins Welsh
University Honors Theses
A capstone project is the culmination of what a student has learned while pursuing an undergraduate degree. A project of this magnitude requires a lot of time and dedication from every member of the team. This essay looks back at the experience of an electrical engineering student participating in the design of an auxiliary power and protection of a planned substation. The author describes the team's work, how they performed as a team, and their involvement with the professional sponsor and advisor. The author examines the experience with the goal of informing and encouraging prospective engineering students who may be …
Designing The Power System Of A Robot, Nolan Hays
Designing The Power System Of A Robot, Nolan Hays
Honors College Theses
This thesis outlines the acquired skills and knowledge acquired through the course of four years of Murray State University’s School of Engineering. The capstone for students in the department was to team up and complete an interdisciplinary senior design project using skills from various tracks of engineering. For this thesis, there is a greater emphasis on the electrical engineering track. The objective of the project was to build an autonomous robot to complete the various tasks within the scope of the IEEE SoutheastCon 2023 Hardware Competition. The robot was controlled via a Raspberry Pi 4 Model B. There were three …
Prediction Of Ka-Band Radar Cross Section With Thz Scale Models With Varying Surface Roughness, Andrew J. Huebner
Prediction Of Ka-Band Radar Cross Section With Thz Scale Models With Varying Surface Roughness, Andrew J. Huebner
Browse all Theses and Dissertations
Radar cross section (RCS) of electrically large targets can be challenging and expensive to measure. The use of scale models to predict the RCS of such large targets saves time and reduces facility requirements. This study investigates Ka-band (27 to 29 GHz) RCS prediction from scale model measurements at 500 to 750 GHz. Firstly, the coherent quasi-monostatic turntable RCS measurement system is demonstrated. Secondly, three aluminum 18:1 scale dihedrals with surface roughness up to 218 icroinches are measured to investigate how the roughness affects the Ka-band prediction. The measurements are compared to a parametric scattering model for the specular response, …
Modeling, Simulation, And Hardware Testing Of A Noise-Canceller Adc Architecture, Ethan R. Rando
Modeling, Simulation, And Hardware Testing Of A Noise-Canceller Adc Architecture, Ethan R. Rando
Browse all Theses and Dissertations
Analog-to-Digital Converters (ADCs) are essential elements of most complex electronic devices. ADCs allow for an analog signal to be converted into the digital domain, and thus interpreted by a digital circuit or model. While ADCs are extremely common, they are not immune from common tradeoffs when being designed and implemented. The most prominent tradeoff when selecting or designing an ADC is whether to pursue a high conversion rate or a high resolution on the digital output. There are some ADC designs that allow for relatively high resolution while maintaining a respectable conversion rate, however these designs often come at the …
Digital Beamforming Array Phase Calibration Techniques For Multi-Pass Interferometric Sar, Kelly Cheung
Digital Beamforming Array Phase Calibration Techniques For Multi-Pass Interferometric Sar, Kelly Cheung
Browse all Theses and Dissertations
Calibration plays a critical role in the optimal performance of algorithms in digital beamforming arrays. Phase incoherency between elements results in poor beamforming with decreased gain and higher sidelobes, leading to a decrease in accuracy and sensitivity of measurements. A similar problem exists in performing multi-pass interferometric SAR (IFSAR) processing of SAR data stacks to generate topological maps of the scene, where phase errors translate to height errors. By treating each SAR image in the data stack like an element of a uniform linear array, this thesis explores several phase calibration techniques that can be used to calibrate digital beamforming …
Multi-Variable Phase And Gain Calibration For Multi-Channel Transmit Signals, Ryan C. Ball
Multi-Variable Phase And Gain Calibration For Multi-Channel Transmit Signals, Ryan C. Ball
Browse all Theses and Dissertations
A method for software-defined radio array calibration is presented. The method implements a matched filter approach to calculate the phase shift between channels. The temporal stability of the system and calibration coefficients are shown through the standard deviation over the course of four weeks. The standard deviation of the phase correction was shown to be less than 2 deg. for most channels in the array and within 8 deg. for the most extreme case. The standard deviation in amplitude scaling was calculated to be less than 0.06 for all channels in the array. The performance of the calibration is evaluated …
Fault Diagnosis And Accommodation In Quadrotor Simultaneous Localization And Mapping Systems, Anthony J. Green
Fault Diagnosis And Accommodation In Quadrotor Simultaneous Localization And Mapping Systems, Anthony J. Green
Browse all Theses and Dissertations
Simultaneous Localization and Mapping (SLAM) is the process of using distance measurements to points in the surrounding environment to build a digital map and perform localization. It has been observed that featureless environments like tunnels or straight hallways will cause positioning faults in SLAM. This research investigates the fault diagnosis and accommodation problem for a laser-rangefinder-based SLAM systems on a quadrotor. A potential solution of using optical flow as velocity estimate and an extended Kalman filter (EKF) to perform position estimation is proposed. A fault diagnosis method for detecting faults in positional SLAM data or optical flow velocity data is …
Merit Study Of Battery Or Hydrogen Energy Storage For Large Scale, Combined Wind And Solar Electricity Generation, Ashley K. Moore
Merit Study Of Battery Or Hydrogen Energy Storage For Large Scale, Combined Wind And Solar Electricity Generation, Ashley K. Moore
Browse all Theses and Dissertations
In the past several years, the energy sector has experienced a rapid increase in renewable energy installations due to declining capital costs for wind turbines, solar panels, and batteries. Wind and solar electricity generation are intermittent in nature which must be considered in an economic analysis if a fair comparison is to be made between electricity supplied from renewables and electricity purchased from the grid. Energy storage reduces curtailment of wind and solar and minimizes electricity purchases from the grid by storing excess electricity and deploying the energy at times when demand exceeds the renewable energy supply. The objective of …
Bandgap Engineering Of 2d Materials And Its Electric And Optical Properties, Kumar Vishal
Bandgap Engineering Of 2d Materials And Its Electric And Optical Properties, Kumar Vishal
Browse all Theses and Dissertations
Since their invention in 1958, Integrated Circuits (ICs) have become increasingly more complex, sophisticated, and useful. As a result, they have worked their way into every aspect of our lives, for example: personal electronic devices, wearable electronics, biomedical sensors, autonomous driving cars, military and defense applications, and artificial intelligence, to name some areas of applications. These examples represent both collectively, and sometimes individually, multi-trillion-dollar markets. However, further development of ICs has been predicted to encounter a performance bottleneck as the mainstream silicon industry, approaches its physical limits. The state-of-the-art of today’s ICs technology will be soon below 3nm. At such …
Current-Source Dc-Dc Converter, Rocio Sanchez-Mendoza, Carlos Aguilar, Adrian Aranjo
Current-Source Dc-Dc Converter, Rocio Sanchez-Mendoza, Carlos Aguilar, Adrian Aranjo
Electrical Engineering
In this project, a hardware implementation of a current-source DC-DC converter for powering sensors used in an underwater communications system is presented. The proposed converter is designed to step down an input current of 0.9 A to 0.625 A, while maintaining an output voltage of 24 V and output power of 15 W. An overview of the system design is explained as well as the component selection process. The design of the converter was simulated and evaluated using LTspice before being physically constructed on a printed circuit board. Performance evaluation of the proposed converter was carried out in multiple lab …
Manual Material Handling Lift-Assist System For Occupational Exoskeleton, Erik Goes, Daniel Guthrie, Trevor Ward
Manual Material Handling Lift-Assist System For Occupational Exoskeleton, Erik Goes, Daniel Guthrie, Trevor Ward
Honors Capstones
It is no secret that lifting heavy objects is one of the premier causes of workplace injury, and the modern worker needs help to remain healthy. Workers need something they always have with them that makes their work safer as well as easier; our solution is an active lift-assist exoskeleton. The proposed exoskeleton design includes a military backpack exoskeleton frame, on which two actuators pull cables attached to end effectors that the operator will be holding. This system can adjust to conform to a wide variety of operator sizes, without restricting any of their range of motion. This leads to …
Enercon Station Vacuum Pump Replacement, Clint Hembree, Jared D'Amico, Connor Moore, Paul Jeffrey Fontenot, Sydnee Castello, J.J. Clements
Enercon Station Vacuum Pump Replacement, Clint Hembree, Jared D'Amico, Connor Moore, Paul Jeffrey Fontenot, Sydnee Castello, J.J. Clements
Senior Design Project For Engineers
This details the progress of the ENERCON pump replacement project as completed by the Kennesaw State University interdisciplinary senior design group. This project is a two-semester capstone effort for the engineering program at Southern Polytechnic School of Engineering, overseen by Dr. McFall during Fall 2020 and Dr. Khalid during Spring 2021 semesters. The 2020-2021 KSU Interdisciplinary Senior Design team was tasked with completing an Engineering Change Package (ECP) for existing vacuum pumps at ENERCON Station. The mechanical, electrical, and civil students worked together, performing evaluations on existing plant systems to ensure the plant could support the new vacuum pumps. By …
Effect Of Cloud Cover On Optimum Orientations Of Fixed Solar Panels For Maximum Yearly Energy Collection, Prethew Prasad
Effect Of Cloud Cover On Optimum Orientations Of Fixed Solar Panels For Maximum Yearly Energy Collection, Prethew Prasad
Browse all Theses and Dissertations
The amount of cloud cover present in the sky is a significant factor when determining the solar radiation impinging on a solar panel. The optimum tilt required to achieve maximum energy impingement on a surface is also influenced by the amount of cloud cover. This work presents a method for determining the optimum tilt angle for a fixed solar panel when a set amount of cloud cover is present in the sky. Fixed tilt angles that have the most incident solar energy over the course of a year as a function of cloud cover, latitude, and azimuthal angle orientation are …
The Theory And Design Of Class E Power Amplifiers For Impulse Excitation In Nuclear Magnetic Resonance, Owen D. Riemer
The Theory And Design Of Class E Power Amplifiers For Impulse Excitation In Nuclear Magnetic Resonance, Owen D. Riemer
Browse all Theses and Dissertations
A new method for analyzing the effectiveness of NMR impulse power amplifiers was developed using a classical linear systems approach to NMR. The method demonstrates a way to compare NMR power amplifiers and outputs. Thermodynamic calculations and the harmonic content of NMR amplifiers is presented to provide a complete description of the NMR power amplifier design problem. A design procedure for class E NMR power amplifiers with a pi-impedance matching network is outlined for matching the amplifier to the transmitter coil. The thesis concludes with the presentation of a 53 MHz power amplifier developed with the procedure. The complete amplifier …
An Improved Method For Hospital Acquired Pressure Ulcer (Hapu) Prevention, Megan Morrissey, Jillian Yeager, Julia Beekman
An Improved Method For Hospital Acquired Pressure Ulcer (Hapu) Prevention, Megan Morrissey, Jillian Yeager, Julia Beekman
Honors Theses
Hospital acquired pressure ulcers (HAPUs), also called bedsores, are damage to the skin and/or underlying tissue caused by prolonged pressure on the bony areas of the body, with around 20% of pressure ulcers occurring in the heel region. Currently, the most common practice for HAPU prevention is arbitrary manual repositioning of patients by nurses every 1-2 hours. The goal of our project was to address HAPUs in the heel region of low mobility patients through an ulceration risk sensing system. Our team has created a wearable ulceration risk assessment system that combines individual patient risk data with real time pressure …
Passive And Active Battery Balancing Methods Implemented On Second Use Lithium-Ion Batteries, Walter Bartek
Passive And Active Battery Balancing Methods Implemented On Second Use Lithium-Ion Batteries, Walter Bartek
Masters Theses
As the number of electric vehicles (EVs) increases, the number of used battery packs that require disposal increases; however, many of these packs still have useful capacity and can be repurposed. When using repurposed large lithium-ion battery packs, deviations between cells within a pack become problematic. These deviations result in a pack that is unbalanced, affecting performance and proving potentially hazardous when charging. Consequently, a battery management system (BMS) is needed. To provide safety, the BMS in this paper monitors and controls the operation of the battery pack. In addition, it controls the redistribution of charge between the cells within …
Quadrotor Uav Flight Control With Integrated Mapping And Path Planning Capabilities, Jason A. Gauthier
Quadrotor Uav Flight Control With Integrated Mapping And Path Planning Capabilities, Jason A. Gauthier
Browse all Theses and Dissertations
Quadrotor UAVs have become a common and easily acquirable hardware platform for research and development with control laws, mapping systems, and path planning. In this research, a non-linear model of a quadrotor UAV is linearized with model parameters being identified using collected flight data. The PID, LQR, and backstepping control laws are implemented. An adaptive control law is also implemented to handle the loss of effectiveness in motor actuation. Additionally, this research also implements a laser-based SLAM algorithm for mapping and localization in an unknown two-dimensional environment. Path planning and obstacle avoidance algorithms are implemented onboard using the Robot Operating …
Tabletop Mechanical Tester, Jamie Dombroski, Brian English, Richard Leffler, Andrew Shirk
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 …
Optimization Study Of A Combined Wind-Solar Farm For A Specified Demand, Venkat Siddhartha Rama
Optimization Study Of A Combined Wind-Solar Farm For A Specified Demand, Venkat Siddhartha Rama
Browse all Theses and Dissertations
At the present time, using wind and solar energy for producing electricity in the United States is becoming cost competitive. According to Lazard’s 2019 [36] levelized cost of energy (LCOE) analysis of a number of energy sources used for producing electricity in the United States, wind and solar are cheaper than natural gas and coal. While capital, maintenance, operation, and fuel costs are included in LCOE numbers, energy source intermittency is not. Intermittency is an important issue with wind and solar energy sources, but not with natural gas or coal energy sources. Combining wind and solar energy sources into one …
Robust Impedance Control Of A Four Degree Of Freedom Exercise Robot, Santino Joseph Bianco
Robust Impedance Control Of A Four Degree Of Freedom Exercise Robot, Santino Joseph Bianco
ETD Archive
The CSU 4OptimX exercise robot provides a platform for future research into advanced exercise and rehabilitation. The robot and its control system will autonomously modify reference trajectories and impedances on the basis of an optimization criterion and physiological feedback. To achieve this goal, a robust impedance control system with trajectory tracking must be implemented as the foundational control scheme. Two control laws will be compared, sliding mode and H-infinity control. The above robust control laws are combined with underlying impedance control laws to overcome uncertain plant model parameters and disturbance anomalies affecting the input signal. The sliding mode control law …
Digital Instantaneous Frequency Measurement Receiver For Fine Frequency And High Sensitivity, Bilal Khudhur Abdulhammed Abdulhamed
Digital Instantaneous Frequency Measurement Receiver For Fine Frequency And High Sensitivity, Bilal Khudhur Abdulhammed Abdulhamed
Browse all Theses and Dissertations
Wideband technology has been applied to many wide bandwidth applications when there is a need to send much different information in a short time from one point and received from another point in high precision and accuracy. A wideband receiver reports a signal without tuning if the signal is within the input bandwidth. The analog Instantaneous Frequency Measurement (IFM) receiver has been used for decades to cover a very wide input bandwidth and report one accurate frequency on a short pulse at a time. The digital IFM use a high sampling rate ADC to operate in a wide bandwidth, Hilbert …
Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam
Opto-Thermal Characterization Of Plasmon And Coupled Lattice Resonances In 2-D Metamaterial Arrays, Vinith Bejugam
Graduate Theses and Dissertations
Growing population and climate change inevitably requires longstanding dependency on sustainable sources of energy that are conducive to ecological balance, economies of scale and reduction of waste heat. Plasmonic-photonic systems are at the forefront of offering a promising path towards efficient light harvesting for enhanced optoelectronics, sensing, and chemical separations. Two-dimensional (2-D) metamaterial arrays of plasmonic nanoparticles arranged in polymer lattices developed herein support thermoplasmonic heating at off-resonances (near infrared, NIR) in addition to regular plasmonic resonances (visible), which extends their applicability compared to random dispersions. Especially, thermal responses of 2-D arrays at coupled lattice resonance (CLR) wavelengths were comparable …
A Transformative Process Control Solution, Simone Castanho Nobrega De Almedia Soares
A Transformative Process Control Solution, Simone Castanho Nobrega De Almedia Soares
ETD Archive
Knowing that a technology invented almost hundred years ago (PID controller) is still dominating industrial process control, a historical review was done to understand how the control field evolved. Model dependency and high level of mathematics appear as the main reasons that prevent other technologies from penetrating the engineering practice. A relatively novel methodology introduced by J. Han in 1998 called Active Disturbance Rejection Control (ADRC) came with characteristics that matches process control needs and restrictions on model dependency. This study will present a transformative solution for process control based on that. The control algorithm is designed and discretized for …
Cyber-Physical Embedded Systems With Transient Supervisory Command And Control: A Framework For Validating Safety Response In Automated Collision Avoidance Systems, Daniel K. Trembley
Cyber-Physical Embedded Systems With Transient Supervisory Command And Control: A Framework For Validating Safety Response In Automated Collision Avoidance Systems, Daniel K. Trembley
Graduate Dissertations and Theses
The ability to design and engineer complex and dynamical Cyber-Physical Systems (CPS) requires a systematic view that requires a definition of level of automation intent for the system. Since CPS covers a diverse range of systemized implementations of smart and intelligent technologies networked within a system of systems (SoS), the terms “smart” and “intelligent” is frequently used in describing systems that perform complex operations with a reduced need of a human-agent. The difference between this research and most papers in publication on CPS is that most other research focuses on the performance of the CPS rather than on the correctness …
Wetting Properties Of Structured Interfaces Composed Of Surface-Attached Spherical Nanoparticles, Bishal Bhattarai
Wetting Properties Of Structured Interfaces Composed Of Surface-Attached Spherical Nanoparticles, Bishal Bhattarai
Browse all Theses and Dissertations
In this thesis, the effects of the external pressure and surface energy on stability and wetting transition at nanotextured interfaces are studied using molecular dynamics and continuum simulations. The surface roughness of the composite interface is modeled via an array of spherical nanoparticles with controlled wettability. It was found that in the absence of external pressure, the liquid interface is flat and its location relative to the solid substrate is determined by the radius of the particle and the local contact angle. With increasing pressure on the liquid film, its interface becomes more curved and the three-phase contact line is …
Chaotic Based Self-Synchronization For Rf Steganography Radar/Communication Waveform, Michael A. Gonnella
Chaotic Based Self-Synchronization For Rf Steganography Radar/Communication Waveform, Michael A. Gonnella
Browse all Theses and Dissertations
In this project, we continue previous CSR project entitled RF Steganography based Joint Radar/Communication Waveform Design to develop a bio-inspired secure low probability detection (LPD) radio frequency (RF) waveform that can serve multiple purposes simultaneously. Previously, we have developed an RF steganography based RF waveform to conceal a secure digital communication within a linear frequency modulated (LFM) chirp radar signal. By exploiting novel reduced phase shift keying modulation and variable symbol duration, the new waveform is resistant to time domain analysis, frequency domain analysis and cyclostationary analysis. However, to demodulate the hidden communication message, the intended receiver has to know …
Wax Bee Gone: A Safe, Effective Solution To Ear Wax Removal, Robert G. Shenon, Shanvir S. Dhinsa
Wax Bee Gone: A Safe, Effective Solution To Ear Wax Removal, Robert G. Shenon, Shanvir S. Dhinsa
Electrical Engineering
This project sought to combine conventional methods such as scraping and water pressure to removal ear wax, but with electronic automation to removal the potential for human error as much as possible. Through the use of a 9V battery, and Arduino microcontroller, DC motors, and other circuitry, this project has developed a prototype for a device that can properly remove ear wax without any discomfort or risk to the user. Much of this project involved learning how to properly manipulate and provide the necessary power requirements DC motors from an Arduino and a 9V battery. Additionally, creating a 3D printed …