Engineering Commons^™

An Investigation Of Soft Electrohydraulic Actuators: Theory, Characterization, And Conceptual Applications, Alexandrea Washington

UNLV Theses, Dissertations, Professional Papers, and Capstones

Electroactive polymer (EAP) materials are a novel soft electromechanical device that exploits the inherent electrical and mechanical advantages of flexible polymer materials. Within this groundbreaking field there are various actuator and sensor devices that have been developed for a variety of applications, from medical devices to artificial biological systems. This research focuses on electrohydraulic actuators, which are comprised of a flexible conductive medium, a dielectric fluid, and a compliant film material to encapsulate the dielectric fluid. This specific study centers around the electrohydraulic EAP actuator known as the Hydraulically Amplified Self-Healing Electrostatic (HASEL) actuator, first introduced by the Keplinger group …

Aerodynamic Implications Of A Bio‐Inspired Rotating Empennage Design For Control Of A Fighter Aircraft, Christian R. Bolander

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation presents an analysis of the aerodynamics for an aircraft using a novel, bio-inspired control system. The control system is a rotating tail, that is inspired by the way in which birds use their tail to control their flight. An aerodynamic model for a baseline aircraft and a bio-inspired variant are created by referencing well-known relationships for the aerodynamics of flight, which are then used to analyze the available flight envelope at which each aircraft can reach two different equilibrium states. An analysis of the total aerodynamic control authority of each aircraft is also included along with a preliminary …

The Influence Of Surface Roughness Frequency On Rotating Sphere Aerodynamics, Jack C. Elliott

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solving the problems of increasing highway fuel efficiency, throwing a better curve ball, and preventing an aircraft from stalling all have a common thread: controlling flow separation. Defined by the fast moving flow around an object detaching from the object, flow separation has implications for a broad number of engineering fields. Research regarding flow separation control has led to the understanding that the easiest method for delaying flow separation for a given shape is to vary how turbulent the flow around the object is. Varying this turbulence around an object may be achieved through various methods including changing the …

Understanding The Effectiveness Between Modern Technologies And Traditional Training Methods Of E-Learning On An Individual’S Learning Curve, Content Retention, And Satisfaction, Andressa Camacho Ortiz

Theses and Dissertations

E-learning has become a widespread and valuable tool for skill development. After the COVID-19 pandemic, the necessity and adaptability of this method increased drastically. Hence, numerous studies focused on understanding the effectiveness of this method. The academic literature highlights the need to explore alternative solutions that can increase a learner’s content retention and satisfaction when learning remotely. Modern technologies can be a great solution for this need with the correct application and development. This thesis analyzes the effects of technology on content retention, satisfaction, and learning curve through the following technologies: online platform, virtual reality (VR), and hologram display. A …

Predicting Near-Bed Sediment Transport Through Particle Image Velocimetry, Caroline Hoch

Theses and Dissertations

Erosion and accretion are coastal processes that directly affect the safety of coastal communities. Dimensionless parameters, such as the Shields and Ursell number, have historically been used to predict sediment motion in the nearshore region based on shear stress and wave linearity. This study uses particle image velocimetry to measure the velocity field of sediment within a wave flume and calculate these parameters for various wave profiles. Five regular wave trials and five irregular wave trials were run within the wave flume at varying depths to model how net transport changes as waves approach the shoreline. An instantaneous Shields number …

Effectiveness Of Rans In Predicting Indoor Airborne Viral Transmission: A Critical Evaluation Against Les, K. Choudhary, K. A. Krishnaprasad, S. Pandey, ‪Nadim Zgheib, J. S. Salinas, M. Y. Ha, S. Balachandar

Mechanical Engineering Faculty Publications

We investigate the dispersal of droplet nuclei inside a canonical room of size 10 × 10 × 3 . 2 m 3 with a four-way cassette air-conditioning unit placed at the center of the ceiling. We use Reynolds averaged Navier–Stokes (RANS) simulations with three flow rates corresponding to air changes per hour (ACH) values of 2.5, 5, and 10. The room setup as well as the operating conditions are chosen to match those of a recent high-fidelity large eddy simulation (LES) study. We use statistical overloading with a total of one million droplet nuclei being initially distributed randomly with uniform …

Experimental And Theoretical Analysis Of Nonlinear Triboelectric Energy Harvester For Frequency Up-Conversion Applications, Hadeel A. Abumarar

Mechanical Engineering Theses

With the development of micro-sensors and wireless applications, energy harvesting has become an effective method for self-powering. However, ambient energy is only limited to below 100Hz, which restricts the energy harvester designs to this range resulting in
an impractical bulky and large-scale harvester. Therefore, in this thesis, we investigated
frequency Up and Down conversion energy harvesters to benefit from the high-frequency oscillations and transferred them to the ambient vibration ranges. Toward this, the triboelectric transduction mechanism has been utilized for a frequency-up conversion for energy harvesting applications, while the piezoelectric transduction mechanism is used for frequency-down
conversion for mass sensing …

Performance Of A Solar Seawater Distillation With A Triangle Prism Cover And A Fin-Type Absorber, Risse Entikaria Rachmanita, Miftah Khoirul Umam

Makara Journal of Technology

Solar-powered distillation is a seawater distillation method that utilizes solar heat as its main energy source for the purpose producing freshwater and a by-product of the distillation process in the form of salt. This study aims to determine the performance of a solar seawater distillation design with a semi-batch system by combining a fin-type absorber plate and a triangular prism cover. This design is equipped with a reflector and absorber plate, which has a surface area of 0.3969 m2 with a volume capacity of seawater that can be accommodated in a basin of ±24 liters. It uses a knockdown system …

Motion Control Simulation Of A Hexapod Robot, Weishu Zhan

Dartmouth College Master’s Theses

This thesis addresses hexapod robot motion control. Insect morphology and locomotion patterns inform the design of a robotic model, and motion control is achieved via trajectory planning and bio-inspired principles. Additionally, deep learning and multi-agent reinforcement learning are employed to train the robot motion control strategy with leg coordination achieves using a multi-agent deep reinforcement learning framework. The thesis makes the following contributions:

First, research on legged robots is synthesized, with a focus on hexapod robot motion control. Insect anatomy analysis informs the hexagonal robot body and three-joint single robotic leg design, which is assembled using SolidWorks. Different gaits are …

Structural Design And Fabrication Of A Test Chamber To Test Ppes For Effective Particle Filtration, Matthew G. Adharsingh

Honors College Theses

This research project aims to design and fabricate a test chamber for testing Personal Protective Equipment (PPE) to ensure effective particle filtration. The chamber has a special purpose, which is to measure ultrafine and submicron particles concentration in the air and test the ergonomic design of PPE based on its effective filtration. The project also considers the environmental aspects of the chamber such as the level of noise and vibration. The chamber will be designed to measure upstream and downstream particle count. Initially, the chamber was going to be made from wood, but the research team encountered difficulties in the …

Recent Developments In Hydrogen Fuel Cell-Powered Drones, Seyed Mohammad Sanjari Pirmahalleh

ATU Scholars Symposium

Hydrogen fuel cells have emerged as a promising alternative to conventional batteries for powering unmanned aerial vehicles (UAVs), also known as drones. In recent years, there has been a significant amount of research and development in hydrogen fuel cell powered drones, with several successful demonstrations and commercial deployments. This research provides a comprehensive review of the recent developments in hydrogen fuel cell technology for UAVs and the current state-of-the-art hydrogen fuel cell powered drones. The research first discusses the advantages of using hydrogen fuel cells in drones, such as higher energy density, longer flight time, and lower environmental impact. It …

Optimization Of Metallic Interconnectors For Clean Energy Power Systems, Mason Cox

Symposium of Student Scholars

The need to eliminate carbon emissions coupled with intensified energy demands have led to an intensified research and development activities in clean energy technology. Taking advantage of fuels such as green hydrogen, solid oxide fuel cells (SOFC) power systems can serve as a potential energy conversion system. SOFCs combine O2 from air and H2 gas to generate electricity, consequently producing water (H2O) as the only byproduct of the electrochemical reaction. SOFCs typically have an operational temperature in the range of 500-900C and generate electricity without the requirement of recharging, so long as the fuel is supplied. A single SOFC cell …

Kayak Automated Steering, Nick Gilbert, Emily Trotter, David Asimbaya, Jorge Garcia, Natalie Nyatsanza

ATU Scholars Symposium

The problem presented is to automate a fishing kayak to make traveling long distances more manageable while maintaining the flexibility, portability, and size of the kayak without making major modifications to the already working item. The proposed design is aimed to solve the steering issues that a fixed seat in a kayak may have and the consistent paddling by supporting them with an automated system. The device is not meant to interfere with the system's manual operation but to provide a sense of aid when needed.

Design And Fabrication Of Gearbox, Mohammed Al Omairi, Ibrahim Alshammari, Nawaf Alshammari, Abdullah Aljohani, Hezam Al Marri

ATU Scholars Symposium

In this project, the gears and other mechanical parts of the gearbox will be created using 3D printing technology, and they will be joined to shafts and combined with ball bearings for smooth motion. This is constructed to make the ideas of gear mechanics and gear shifting simple to visualize and comprehend.

The Aerocap Aerodynamic Attachment For Pickup Trucks, Andrew J. Tucker, David Silk

ATU Scholars Symposium

As the pickup truck continuously becomes more popular in both commercial and family applications, the fuel efficiency of modern pickup design should be brought into question. According to CBS News, pickup trucks accounted for around 20% of all new vehicles sold in America in 2022, with the three most popular vehicles sold during the year all being pickups. However, these vehicles consistently have higher drag coefficients than other types of vehicles, namely sedans or crossovers. This leads to decreased fuel economy and more overall greenhouse gas emissions. Even in the case of an electric pickup truck, the high drag coefficient …

Rc Flying Car, Andrew Hood, Ethan Jacobs, Nicholas Jones, Joshua Phifer

ATU Scholars Symposium

For this project, the goal is to build a 3D printed RC flying car with actuating wings and to show the modularity and adaptability of using 3D printing to create a multifunctional RC flying car. The goal with the actuating wings is to showcase how adaptable and modular 3D printing is and to also have a drivable car. Also, with a multifunctional 3D printed flying car, an end user could customize the flying car to their desired needs or wants. The reason for choosing to build a flying car instead of just a plane or a car is that it …

Demonstration Of Hydrogen Combustion Properties, Stephen M. Baker

ATU Scholars Symposium

The Hydrogen Flame Demonstration project encompasses the design, fabrication, and usage of a pressure vessel system with the goal of demonstrating the hazardous flammable properties that are associated with gaseous hydrogen. This project was completed as a part of a 16-week internship at the NASA White Sands Test Facility in Las Cruces, New Mexico during the Spring of 2022. As the interest of technologies using hydrogen as a fuel, or otherwise, increases, informing and setting ‘best practices’ for use of pressure systems containing hydrogen becomes increasingly necessary. Gaseous hydrogen is highly flammable with the presence of air or oxygen. Since …

Functional Integrated Storage Housing, Noah M. Disheroon, Christopher Dew, Andrew L. Hilsdon, Vana Ducusin, Thomas Dodds, Alexander J. Holland

ATU Scholars Symposium

The vertical rotating shelf is a new design concept for a robotics laboratory that provides a compact and efficient storage solution for a variety of components and materials. The shelf is designed to maximize storage capacity while minimizing the amount of space required. The shelf consists of a sturdy metal frame with multiple shelves attached to it. The shelves are modular and the bins on the shelves can be changed to accommodate items of varying sizes. The rotating mechanism is powered by a motor, which allows for easy access to all items on the shelf without having to move or …

Optical Fiber Tip Micro Anemometer, Jeremiah C. Williams, Hengky Chandrahalim

AFIT Patents

A passive microscopic flow sensor includes a three-dimensional microscopic optical structure formed on a cleaved tip of an optical fiber. The three-dimensional microscopic optical structure includes a post attached off-center to and extending longitudinally from the cleaved tip of the optical fiber. A rotor of the three-dimensional microscopic optical structure is received for rotation on the post. The rotor has more than one blade. Each blade has a reflective undersurface that reflects a light signal back through the optical fiber when center aligned with the optical fiber, the blades of the rotor shaped to rotate at a rate related to …

Spatiotemporal Prediction Of Microstructure Evolution With Predictive Recurrent Neural Network, Amir Abbas Kazemzadeh Farizhandi, Mahmood Mamivand

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Prediction of microstructure evolution during material processing is essential to control the material properties. Simulation tools for microstructure evolution prediction based on physical concepts are computationally expensive and time-consuming. Therefore, they are not practical when either there is an urgent need for microstructure morphology during the process or there is a need to generate big microstructure datasets. Essentially, microstructure evolution prediction is a spatiotemporal sequence prediction problem, where the prediction of material microstructure is difficult due to different process histories and chemistry. We propose a Predictive Recurrent Neural Network (PredRNN) model for the microstructure prediction, which extends the inner-layer transition …

Base Vibration Effects On Additive Manufactured Part Quality, N. J. Jensen, G. G. Parker, J. R. Blough

Michigan Tech Publications, Part 1

Additive Manufacturing (AM) has opened the door for portable and self-sufficient fabrication. However, environments with base vibration degrade part quality during production. This work focuses on investigating and mitigating the effects of base vibration on AM part quality. Factors influencing part quality initiated the approach, followed by experiments on an extrusion-type printer to inspect and minimize vibration effects. Part roughness was used as the part quality metric based on preliminary experimental observations. A modal impact test identified the print bed and print head gantry as vibration-sensitive components at ≈ 40 Hz. These vibration modes were targeted with experiments to evaluate …

Shape Memory Polymer-Based Multifunctional Syntactic Foams, Siavash Sarrafan

LSU Doctoral Dissertations

With the increase in popularity of shape memory polymers (SMPs), especially in applications such as aerospace, textile, biomedical engineering, and even structures, the weight of the material and the devices made with it has always been a crucial factor. Using the shape memory polymer as a matrix to make a syntactic foam is one of the best and most affordable approaches to creating a lighter material that still has the shape memory effect. The addition of particles of different stiffness, strength, and size, with variable fractions, creates a composite that enables engineering the mechanical, as well as other physical and …

Design And Development Of Magnetoelastic Resonators For Pv Ground Fault Detection, Skyler H. Oglesby

Mechanical Engineering ETDs

This project will design, fabricate, and test a magnetoelastic nickel-iron-cobalt alloy resonator for ground fault detection applications, specifically in photovoltaic systems. The electrodeposition technique will be used to fabricate the proposed resonator as it enables a precise manufacturing process. It allows for better control and optimization of material properties (magnetic, mechanical, and electrical) while facilitating the necessary dimensions. A great deal of study and experimentation will go into the electrolyte development when dealing with challenges like intrinsic stress and surface defects within the film. Hull cell analysis will be done to study the composition of the material in different electrochemical …

Servo Mounting Device And Collective Control System Design For The Forward Flight Aero Test Stand, Aaron Jones

NASA-Missouri Space Grant Consortium

The majority of the ten-week internship was spent designing a servo mounting device, and a collective control system for the Forward Flight Aero Test (FFAT) stand. The servo mounting device uses four threaded standoffs along with a top plate, held together with screws, that raises the servos above the protruding threaded rods and screws. The collective control system is a rectangular block that attaches the swashplate to the servo arms connected to the servo motor. This control rod is used to translate the rotation from the servo arm into collective control for the blade angle. The control rod has two …

An Introductory Investigation Of Dust Devils On Mars: Computational Fluid Dynamics Modeling, Alexios Nicolas Philippou, Kakkattukuzhy M. Issac

NASA-Missouri Space Grant Consortium

This report investigates the flow characteristics of tornado like vortices which can be used to describe an array of axisymmetric rotating vertical columns of fluid such as dust devils, steam devils and tornadoes. These vortices have been recreated within vortex chambers in research facilities, but in focus of this report the investigation is conducted through numerical simulations using the Computational Fluid Dynamics (CFD) software package provided by ANSYS. By varying the main governing nondimensional parameter of swirl ratio through the computational domain’s boundary conditions, different flow characteristics appear which confirm theories presented in previous papers. This enables the research conducted …

Modeling And Simulation Of An Electrostatic Lunar Particle Sieve, Aaron Berkhoff

NASA-Missouri Space Grant Consortium

The following research was conducted to develop a kinetic particle model, which simulates an electromagnetic sieve used for in-situ material utilization on the lunar surface. A code package was developed to simulate an electromagnetic sieve that uses electrodes to transport fine particles within a cylindrical device. Specifically, this research generates an initial working model for the sieve and tests different electrode configurations. The simulation models different electric fields generated by electrodes, kinetic particle dynamics, and lunar particle distribution. During the case study, which investigates different electrode configurations, it was determined that electrodes oriented such that electrodes located above and below …

Nationwide Eclipse Ballooning Project: April 2023 Status Report, Jill Schmidt

NASA-Missouri Space Grant Consortium

This report details the progress of the Missouri S&T Nationwide Eclipse Ballooning Project as of April 2023 and the future work the team will complete throughout the remainder of 2023 and 2024. This project began in January 2023, and students have been completing preliminary training activities, so they are prepared to begin assembling and testing the eclipse payloads during summer 2023. Throughout the summer, all team members will be actively engaged in this research project and participating in outreach events related to high altitude ballooning.

High Pressure Injection Process For Ceramic Composites, Samuel Weiler

NASA-Missouri Space Grant Consortium

Ceramic materials are valued for good heat resistance and corrosion resistance. Due to these benefits, they are widely used in the aviation, automotive, medical, construction, and other industries. Ceramic materials are also both hard and brittle, qualities that are not ideal in many applications. To reduce brittleness, and other undesirable characteristics of ceramics, engineers have turned to composites to increase the mechanical properties of these materials. By adding composite particles or fibers, these characteristics can be improved. Constructing ceramic composites is not without its challenges, however. Current processes are prone to high porosity, high shrinkage, and poor accuracy of parts. …

Performance Evaluation Of Additively Manufactured Carbon/Peek Composites, Matik S. Heskin

NASA-Missouri Space Grant Consortium

Carbon/PEEK composites have a broad range of applications due to their combinations of superior creep properties and excellent strength to weight ratios. Like all fiber-based composites they are limited geometrically by their required manufacturing processes. Additively manufactured (AM) materials overcome this issue and can be formed into incredibly complex shapes. By combining these two fields, a material limited in application by geometry can have its shortcomings supported with AM processes.

AM carbon/PEEK composites have already been created but this relatively new material still needs property characterization. Therefore, the objective of this work will be to evaluate the structural performance of …

From Land Grant To Space Grant, Mohammad Dehghani

NASA-Missouri Space Grant Consortium

No abstract provided.