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Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon 2024 California Polytechnic State University, San Luis Obispo

Hitch Cart “Landing Gear”, Rebekah White, Jose Raygoza, Randy Hernandez, Brandon Leon

Mechanical Engineering

This report aims to allow our sponsor, to review our design process of the Hitch Cart Landing Gear Prototype. In the design overview section of this report, we discuss the primary design modifications we made to the wheel mechanism of the existing hitch cart prototype, including the addition of the ACME screws and the folding brackets. This allows our sponsor to see the intended improvements made to the past prototype and understand the primary goal of our project. Then, in the implementation section, we cover the entire manufacturing process to allow our sponsor to understand what manufacturing steps must be …


Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb 2024 American University in Cairo

Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb

Theses and Dissertations

Implantable drug delivery devices have many benefits over traditional drug administration techniques and have attracted a lot of attention in recent years. By delivering the medication directly to the tissue, they enable the use of larger localized concentrations, enhancing the efficacy of the treatment. Passive-release drug delivery systems, one of the various ways to provide medication, are great inventions. However, they cannot dispense the medication on demand since they are nonprogrammable. Therefore, active actuators are more advantageous in delivery applications. Smart material actuators, however, have greatly increased in popularity for manufacturing wearable and implantable micropumps due to their high energy …


Comparative Life Cycle Assessment Of Recycling Processes For Perovskite Solar Cells, Juan P. Herrera, Jules Freeman, Achyuth Ravilla, Ilke Celik 2024 Portland State University

Comparative Life Cycle Assessment Of Recycling Processes For Perovskite Solar Cells, Juan P. Herrera, Jules Freeman, Achyuth Ravilla, Ilke Celik

Student Research Symposium

Perovskite solar cells (PSCs) have emerged as a promising option for solar energy generation. However, it is essential to consider the environmental impact of these innovative photovoltaic (PV) technologies as the industry moves towards commercialization. Researchers are currently exploring ways to recycle PSCs to recover valuable materials and reduce their environmental impact at the end of their life. To ensure the sustainability of PSCs, this study evaluates and compares the environmental impacts of five recently developed recycling approaches. The Tool for Reduction and Assessment of Chemicals (TRACI) method was utilized to measure environmental impacts in categories such as acidification (kg …


Pulse Modulation In Braided Pneumatic Actuators Mimics Contractile Behavior Of Biological Muscles, Mohamad Elzein 2024 Portland State University

Pulse Modulation In Braided Pneumatic Actuators Mimics Contractile Behavior Of Biological Muscles, Mohamad Elzein

Student Research Symposium

Advancements in robotics and bioengineering aim to emulate biological muscle systems through robotic actuators, blending mechanical strength with biological adaptability. A lesser-explored aspect is mimicking the pulse-like control characteristic of biological muscles, which contract in response to action potentials from motoneurons, with muscle contractile force relying heavily on the timing between these potentials. This study explores the effect of pulse lengths and the gaps between pulses on braided pneumatic actuators (BPAs), which mimic the nonlinearity and dynamic response of biological muscles. It hypothesizes that artificial muscles utilizing pulse-based control will exhibit a similar force dependency on the intervals between pulses …


Deriving Analytical Design Constraints For Absolute & Relative Encoding Schemes In Functional Subnetworks, Cody W. Scharzenberger-Braet, Alexander Hunt 2024 Portland State University

Deriving Analytical Design Constraints For Absolute & Relative Encoding Schemes In Functional Subnetworks, Cody W. Scharzenberger-Braet, Alexander Hunt

Student Research Symposium

As neural networks have become prolific solutions to modern problems, there has been a congruent rise in the popularity of the numerical machine learning techniques used to design them. While they are highly generalizable, numerical methods tend to produce networks that act as inscrutable “black boxes,” making it difficult to interpret their behavior. One solution to the problem of network transparency is to use analytical techniques, but these methods are underdeveloped compared to their numerical alternatives. In order to enhance the viability of analytical techniques, this work extends previous efforts to quantify the impact that non-spiking neural encoding schemes have …


Analyzing Heat Generated From Electro-Osmotic Flow Utilizing Computational Fluid Dynamics, Jordan Elizabeth Grothe 2024 University of South Dakota

Analyzing Heat Generated From Electro-Osmotic Flow Utilizing Computational Fluid Dynamics, Jordan Elizabeth Grothe

Honors Thesis

Without extensive vascularization, the transfer of fluid and nutrients through human tissue is limited to diffusion and weak interstitial flow. Electroosmosis, or the flow of fluid driven by an electrical field, has become a promising solution. Scientists have begun applying electricity to human tissue to promote stronger interstitial flow; however, optimization of this process has proven to be a challenge due to ohmic heating. Cells function within a small range of temperatures and exposure to voltages exceeding the threshold will cause cells to degrade and die prematurely. This research seeks to better understand and quantify the range of voltage where …


Development, Modeling, Identification, And Control Of Tilt-Rotor Evtol Aircraft, Clayton T. Spencer 2024 Utah State University

Development, Modeling, Identification, And Control Of Tilt-Rotor Evtol Aircraft, Clayton T. Spencer

All Graduate Theses and Dissertations, Fall 2023 to Present

This thesis includes the development, modeling, identification, and control of an electric-Vertical-Take-Off-and-Landing (eVTOL) aircraft with tiltable rotors. The front two rotors have tilting capability for transition flight from vertical-take-off to forward-level flight. This work details the development of an eVTOL aircraft and the selection of sub components such as electric motors, batteries, and controllers. After the aircraft build, mathematical model is derived to describe the motion of the aircraft. Unknown parameters in the mathematical model are identified using a Least-Squares-regression (LSR) method that can handle parameter constraints. This is done using real flight data collected from the aircraft. Lastly, this …


Test And Evaluation Model For Midwater Docking Of Autonomous Underwater Vehicles, Parker Baillon 2024 Florida Institute of Technology

Test And Evaluation Model For Midwater Docking Of Autonomous Underwater Vehicles, Parker Baillon

Theses and Dissertations

This research created a Test and Evaluation (T&E) model for midwater Autonomous Underwater Vehicle (AUV) capture. The creation of this model will allow for a better assessment of the feasibility of midwater AUV capture. To achieve this, the T&E model was exposed to various flow conditions to assess stability. Capturing an AUV in midwater, the area below the wave-affected zone to the sea floor, has many benefits for an AUV and its mission. AUVs basing missions from a midwater dock will not be affected by wave motions. A midwater dock can be transported to any mission site and deployed with …


Mechanical Properties And Microstructure Of Multi-Materials Fabricated Through A Combination Of Lpbf And Ded Additive Manufacturing Techniques, Christopher J. Bettencourt 2024 Utah State University

Mechanical Properties And Microstructure Of Multi-Materials Fabricated Through A Combination Of Lpbf And Ded Additive Manufacturing Techniques, Christopher J. Bettencourt

All Graduate Theses and Dissertations, Fall 2023 to Present

This research explores the use of different metals combined through 3D-printing to enhance the performance of materials, with a focus on making heat exchangers more cost-effective for renewable energy. The goal is to replace a costly high-temperature alloy with a more affordable low-temperature alloy, using metal additive manufacturing for its benefits such as less material waste, faster production, reduced weight, and the ability to print entire assemblies in one go. The study delves into a unique combination of two 3D-printing techniques, Directed Energy Deposition and Laser Powder-Bed Fusion, to create a multi-material composed of stainless steel 316L and a nickel-based …


Rasc-Al Large Scale Lunar Crater Prospector, Austin Arnold, Coleman Alvarez, Mark Suberu 2024 Kennesaw State University

Rasc-Al Large Scale Lunar Crater Prospector, Austin Arnold, Coleman Alvarez, Mark Suberu

Senior Design Project For Engineers

The purpose of this project is to design a conceptual layout of a lunar rover capable of exploring craters at the lunar south pole. The rover should be autonomous and capable of self-sustainment for at least one year in extreme cold and darkness. While determining the location and accessibility of water ice and other volatiles within the crater. This document will contain all information related to the team's conceptual design. Including research, component selection, electrical design, and mechanical design.

Lunar Rascals Video: https://www.youtube.com/watch?v=MdcjzVMtzaI


Modeling Vibration Stiffness: An Analytical Extension Of Hertzian Theory For Angular Contact Bearings With A Thin Viscoelastic Coating, Davis R. Burton 2024 Harding University

Modeling Vibration Stiffness: An Analytical Extension Of Hertzian Theory For Angular Contact Bearings With A Thin Viscoelastic Coating, Davis R. Burton

Honors Theses

This thesis considers the novel angular contact rolling-element bearings proposed by NASA’s Glenn Research Center, which are coated with a thin solid lubricant that exhibits viscoelastic behavior. Current analytical models for the dynamic stiffness matrix of angular contact bearings, critical for vibration analysis, lack the ability to model the effects of a solid coating, as well as the time dependencies inherent in viscoelastic theory. The author first presents an overview of the stiffness matrix derivation, followed by a treatment of the underlying Hertzian contact theory. An analytical extension of this theory is proposed which accounts for a thin elastic layer …


Summonable Construction Delivery Robot, Kevin M. Lewis 2024 Northern Illinois University

Summonable Construction Delivery Robot, Kevin M. Lewis

Honors Capstones

In many different construction industries, there is a need for tools, parts, and other necessary items to be transported quickly and efficiently over various types of terrain. Human resources have often been used to address these needs, which can become very time and cost inefficient over long periods. The design proposal here is aimed at addressing this need by developing an autonomous outdoor mobile robot based on a quadrupedal robot design. This approach differs by incorporating a wheeled and quadrupedal hybrid actuation system that provides terrain negotiation and speed at the appropriate times. The team uses Robot Operating System (ROS) …


The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough 2024 University of Arkansas, Fayetteville

The Analysis Of Mechanical Exfoliation Of Graphene For Various Fabrication And Automation Techniques, Lance Yarbrough

Mechanical Engineering Undergraduate Honors Theses

Mechanical Exfoliation of Graphene is an often-overlooked portion of the fabrication of quantum devices, and to create more devices quickly, optimizing this process to generate better flakes is critical. In addition, it would be valuable to simulate test pulls quickly, to gain insight on flake quality of various materials and exfoliation conditions. Physical pulls of graphene at various temperatures, pull forces, and pull repetitions were analyzed and compared to the results of ANSYS simulations, solved for similar results. Using ANSYS’ ability to predict trends in exfoliations, flake thickness and coverage using stress and deflection analyses were investigated. Generally, both strongly …


Large Eddy Simulation Of Fluid Mixing In Migadome Facility For The Astfe Nuclear Thermal Hydraulics Cfd Competition, Kolten Strauss 2024 University of Arkansas, Fayetteville

Large Eddy Simulation Of Fluid Mixing In Migadome Facility For The Astfe Nuclear Thermal Hydraulics Cfd Competition, Kolten Strauss

Mechanical Engineering Undergraduate Honors Theses

This paper is a documentation of a submission to the First Annual ASTFE Nuclear Thermal Hydraulics Computational Fluid Dynamics (CFD) Competition [1]. To validate simulations of turbulent mixing in buoyancy-driven flows, an air and argon test case was set up inside the University of Michigan’s MiGaDome mixing vessel. This submission to the competition used a polyhedral mesh of about two and a half hundred thousand cells, a Large Eddy Simulation (LES) of the MiGaDome, and the Wall-Adapting Local Eddy-viscosity (WALE) subgrid approximation model. The competition included a factor considering the energy cost of our simulations, so it was decided to …


Flow Characterization With Acoustic Emission Sensing, Jackson Marsh 2024 University of Arkansas, Fayetteville

Flow Characterization With Acoustic Emission Sensing, Jackson Marsh

Mechanical Engineering Undergraduate Honors Theses

Acoustic emissions (AE) allow for non-intrusive sensing into many types of systems. In systems where there is flow of some type, AE is very useful as these types of systems can be characterized in many ways from the collisions or creation of the flow. Correctly setting up the AE system is extremely important. Failure to do so results in imprecision and inaccurate data being collected. Because of this synchronization techniques, sensor configurations, and data acquisition systems must all align. This can be done with off-the-shelf, commercial systems, but this does not allow for customization and the ability to tailor the …


Model-Based Comparison Of Biological Organism And Electro-Mechanical System Resiliency Strategies, Nicholas Ratycz 2024 University of Arkansas, Fayetteville

Model-Based Comparison Of Biological Organism And Electro-Mechanical System Resiliency Strategies, Nicholas Ratycz

Mechanical Engineering Undergraduate Honors Theses

Bio-inspired design has been used by many engineers to solve difficult problems or to make manufacturing processes more efficient. Biomimetics is the study of implementing the structure or function of biological substances, materials, mechanisms, and processes onto artificial ones that mimic the original. The goal of the BIASD tool is to provide bio-inspiration for engineers by studying the fault-adaptive strategies that biological systems use, rather than just their structure or function. In this thesis, the fault adaptive strategies of both a biological example and that of a real cubesat are compared using three types of model-based system diagrams to show …


Comparative Analysis Of Command Protocols For Cubesat Data Handling Systems, Roman Dowling 2024 University of Arkansas, Fayetteville

Comparative Analysis Of Command Protocols For Cubesat Data Handling Systems, Roman Dowling

Mechanical Engineering Undergraduate Honors Theses

Researchers at the University of Arkansas developed ARKSAT-1, a cubic satellite with the purpose of employing an LED with a tracking system to perform spectroscopic measurements of the atmosphere.

The control board of the satellite contained several microcontrollers which worked in concert to collect and manage data. Discussed in this report are the software programs developed for the microcontrollers, dual Arduino MKRZeros, utilized as data repositories and for control of satellite peripherals. The programs discussed in this project include an original existing command-response protocol and an improved batch-command protocol, each with its accompanying data handling and storage system. These programs …


Cam And Design For Manufacturing: Developing A Project-Based Learning Course, Stephen Pierson 2024 University of Arkansas, Fayetteville

Cam And Design For Manufacturing: Developing A Project-Based Learning Course, Stephen Pierson

Mechanical Engineering Undergraduate Honors Theses

To effectively serve student career success, mechanical engineering programs must teach students how to account for manufacturing considerations in design. Despite this, manufacturing education is a glaring area of need in current engineering curricula. In fact, basic manufacturing knowledge is one of the only hard skills consistently ranked as one of the greatest weaknesses of mechanical engineering hires in surveys of industrial employers over the last few decades. Without radically changing departmental curriculum to include more emphasis on design-build projects, one solution to combat this is to incubate a lab course in mechanical engineering programs in which undergraduates would practice …


Experimental And Numerical Investigation Of Air-Cooled Heat Sinks, Ethan Weems 2024 University of Arkansas, Fayetteville

Experimental And Numerical Investigation Of Air-Cooled Heat Sinks, Ethan Weems

Mechanical Engineering Undergraduate Honors Theses

Lightweight and affordable cooling capabilities are critical as the physical scale of electronics continues to decrease. Air-cooled heat sinks that dissipate heat from electronic components to the surrounding air are excellent candidates to fill this role. While plate-fin and pin-fin heat sinks have been implemented extensively for electronic cooling, recent advances in additive manufacturing enable the fabrication of more complex structures. In this undergraduate Honors thesis, a means by which to generate novel heat sink geometries is presented. To that end, an experimental characterization facility is developed to evaluate existing traditional heat sinks. The heat transfer performance of the heat …


Renewable Energy Misinformation: A Literature Based Approach To Rebutting False Claims, Matthew Ard 2024 San Jose State University

Renewable Energy Misinformation: A Literature Based Approach To Rebutting False Claims, Matthew Ard

McNair Research Journal SJSU

No abstract provided.


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