Mechanical Engineering Commons^™

A One-Dimensional Volcanic Plume Model For Predicting Ash Aggregation, D. W. Hoffman, L. G. Mastin, Alexa R. Van Eaton, Stephen Solovitz, Raul Bayoan Cal, J. K. Eaton

Mechanical and Materials Engineering Faculty Publications and Presentations

During explosive volcanic eruptions, volcanic ash is ejected into the atmosphere, impacting aircraft safety and downwind communities. These volcanic clouds tend to be dominated by fine ash (μm in diameter), permitting transport over hundreds to thousands of kilometers. However, field observations show that much of this fine ash aggregates into clusters or pellets with faster settling velocities than individual particles. Models of ash transport and deposition require an understanding of aggregation processes, which depend on factors like moisture content and local particle collision rates. In this study, we develop a Plume Model for Aggregate Prediction, a one-dimensional (1D) volcanic plume …

Cellulose Materials For Drug Delivery Applications, Reham Mohamed

Mechanical Engineering Theses

Non-healing wounds are a growing global public health concern due to inadequate or ineffective therapeutic products available. Cellulose-based biopolymers are attractive wound dressing materials due to their biocompatibility, biodegradability, non-toxicity, and cost-effectiveness. This study aims to design and fabricate solid dosage formulations using carboxymethyl cellulose (CMC) and ethyl cellulose (EC) to facilitate multi-stage releases of phenytoin (PHT) and tetracycline hydrochloride (TCH) from plain carriers, fibers/films composites, and layer-by-layer fiber composites. Results from in vitro drug release assays demonstrated a time-dependent release up to 8 hours from PHT-loaded EC fibers, while TCH-loaded CMC films exhibited a rapid release within 5 minutes. …

Additive Manufacturing And Characterization Of Auxetic Structures, Jayesh P. Moore, Stephanie R. Ruzicka

College of Engineering Summer Undergraduate Research Program

An auxetic structure is an arrangement of unit cells that under a uniaxial load experiences expansion in both the longitudinal and transverse directions, resulting in a negative Poisson’s ratio (NPR). Research in auxetics has led to new insights into how non-linear mechanical reactions can be applied to various engineering fields. This project utilized stereolithography (SLA) 3D printing to manufacture auxetic test specimens to analyze of geometry-driven NPRs. With the distinctive mechanical properties of auxetic structures and vast applications, the future of product development of these geometries seems promising.

Hardware-In-The-Loop Reaction Wheel Testbed With Camera Vision, Abigail Romero, Harvey Perkins, Stephen Kwok-Choon

College of Engineering Summer Undergraduate Research Program

Reaction wheels are widely used in aerospace systems as a method of attitude control. This research was focused on the design, development, and testing of a hardware-in-the-loop reaction wheel testbed that can be used for research and teaching applications related to satellite navigation and control. This project successfully utilized commercial off-the-shelf components to develop a reaction wheel capable of controlling the orientation of a freely rotating platform, as well as tracking objects using computer vision.

Additive Manufacturing For Medical Education, Michael Noon

College of Engineering Summer Undergraduate Research Program

A growing body of evidence is suggesting that anatomical knowledge, the keystone of many medical specialties, is suffering among new graduates. While a host of reasons are provided, one common thread that many point to is the decline of cadaver dissections in the classroom. Many virtual audio-visual tools are used to address this gap, yet evidence has shown their ineffectiveness. Given this gap, the high degree of flexibility found in additive manufacturing (AM), and the many uses AM has already found in the medical field, we propose its use to fill this gap, allowing for students to learn with touch …

Review Study On Promoting Diversity And Inclusion In Engineering Education Through Digital Twins, Devon Bountry

College of Engineering Summer Undergraduate Research Program

This study investigates the effect of digital twins in engineering education. This research was based on published research papers, conference papers, and case studies. Throughout a large range of studies, it was shown that digital twins can increase learning motivation and retainment through uses such as game-centered learning, personalized learning, and virtual prototyping. Particularly in engineering laboratory classes, digital twins can increase the variety of laboratory options while not increasing the cost due to equipment. This results in less barriers for students as there are more learning tools available at no additional cost or other requirements.

Development Of Pullulan/Chitosan/Salvianolic Acid Ternary Fibrous Membranes And Their Potential For Chemotherapeutic Applications, Salahuddin Ahmed, Megan Keniry, Victoria Padilla, Narcedalia Anaya-Barbosa, Md Noushad Javed, Robert Gilkerson, Kithzia Gomez, Acharan S. Narula, Karen Lozano

Mechanical Engineering Faculty Publications

This study investigates the feasibility of centrifugal spinning for producing fibrous membranes containing pullulan, chitosan, and danshen extract. The danshen extract is composed of 20 wt% salvianolic acid B (SA). Citric acid was added to the mixture as a crosslinking agent to promote its use in the aqueous medium. The influence of the danshen concentration (25 wt% and 33 wt%) on fiber morphology, thermal behavior, and the biochemical effect was analyzed. Developed fiber-based membranes consist of long, continuous, and uniform fibers with a sparse scattering of beads. Fiber diameter analysis shows values ranging from 384 ± 123 nm to 644 …

The Investigation Of A Likely Scenario For Natural Tornado Genesis And Evolution From An Initial Instability Profile, Alexios Nicolas Philippou, Kakkattukuzhy M. Isaac

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A likely mechanism for the little-understood tornado genesis is proposed and its numerical implementation is presented. The Burgers-Rott vortex with its axis in the vertical direction is introduced as an instability mechanism, and the flow field then evolves under the influence of the atmospheric pressure, temperature and density variations with altitude. Buoyancy effects are implemented using the Boussinesq model. Results are presented and discussed for a set of conditions including mesh type and size, different turbulence models, and a few different boundary conditions. Post-processed results of the transient simulations including animations contain a wealth of information to help analyze tornado …

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 …

Effect Of Room Size, Shape, Ac Placement, And Air Leakage On Indoor Airborne Viral Transmission, K. Choudhary, K. A. Krishnaprasad, ‪Nadim Zgheib, M. Y. Ha, S. Balachandar

Mechanical Engineering Faculty Publications

Highlights

• Statistical overloading is used to obtain spatio-temporal pathogen concentration.

• Symmetrically placed AC limits pathogen propagation over long distances.

• Well-mixed model captures room-averaged concentration for any shape and AC location.

• The pathogens level of mixing is reduced when AC is symmetrically positioned.

• Air leakage has insignificant impact on indoor pathogen distribution.

Abstract

We conducted Euler–Lagrange Reynolds-Averaged Navier–Stokes simulations with statistical overloading to investigate the effect of room shape, air-condition (AC) location, and the presence of an open window on indoor airborne viral transmission, particularly as it relates to the spatio-temporal distribution of viral-laden droplet nuclei. Two room geometries were …

Development Of Prediction Method For Dimensional Stability Of 3d-Printed Objects, Kyung-Eun Min, Jae-Won Jang, Jesik Shin, Cheolhee Kim, Sung Yi

Mechanical and Materials Engineering Faculty Publications and Presentations

Fused deposition modeling (FDM), as one of the additive manufacturing processes, is known for strong layer adhesion suitable for prototypes and end-use items. This study used a multiple regression model and statistical analysis to explore the dimensional accuracy of FDM objects. Factors such as inclination angle, layer thickness, support space, and raster angle were examined. Machine learning models (Gaussian process regression (GPR), support vector machines (SVM), and artificial neural network (ANN)) predicted dimensions using 81 datapoints. The mean squared dimensional error (MSDE) between the measured and designed surface profiles was selected as an output for the dimensional accuracy. Support spacing, …

Mems 411: B8-Golf Striker, Theodore Francis Anastasoff, Mitchell Oswald Shannon, Aidan Richard Tierney, Nick Alexander Vazquez

Mechanical Engineering Design Project Class

Robots are useful for a variety of tasks and can be very fun to make. For our design of a golf striker robot, we will use our knowledge of core mechanical engineering principles to achieve our goal of a functional end product. Our research into existing devices of such nature showed us how useful these robots are in the golf industry. Whether it is to see how far technology ad machine learning has evolved or to test how golf equipment will stand under duress, these robots provide useful feedback for companies and players. Seeing devices like Golfi, LDRICK, and the …

Mems 411: Waterproof Enclosure For Smart Shirt Microcontroller, Josh Towns, Eric Montufar-Morales, Jacob Williams

Mechanical Engineering Design Project Class

The purpose of this project was to create an enclosure for a microcontroller for an electronic shirt, made by Dr. Mary Ruppert-Stroescu. The electronic shirt was made to help people with sleep apnea track their EKG, blood pressure, and heart rate in an easy and non-invasive way.

The current design being used has sharp edges and is not very secure. The goal of our new design was to make the enclosure comfortable to the wearer while also maintaining a water tight seal. This was done through multiple iterations of rounded enclosures with different gaskets. The end design was a two …

Mems 411: Swing Energy Demo, Joshua Yoon, Owen Culver, Angel Wan, Gabriel Myong

Mechanical Engineering Design Project Class

A device to demonstrate the energy processes of a swing was created with the intention of display at the St. Louis Science Center.

Mems 411: Smart Shirt Electronics Housing, Nickolas Allen, Aaron Deleon, Dominic Fulginiti

Mechanical Engineering Design Project Class

Millions of Americans suffer from sleep apnea, a chronic condition that can impact the quality of sleep and livelihood of those impacted by it. The sleep tests that are performed to see if a patient has sleep apnea are very invasive to those that undergo them, but the WUSTL Smart Shirt removes the need for such tests. This biometric shirt contains electrodes that measure blood pressure, heart rates, and EKG diagnostics that create reports to determine if the patient has sleep apnea, removing the need for the invasive sleep tests for a diagnosis. We were tasked with making the electronics …

Mems 411: Piston Pong, Lauren Faust, Emma Kroll, Natalie Fisher, Caroline Ferry

Mechanical Engineering Design Project Class

This report documents the design process of our ”Piston Pong” device. Our device was designed to be an educational demonstration of pneumatics and energy transformations using work and fluids models. The concept is that a bike pump will pump air into a holding container. After enough pressure is built up inside, the air will be released from the holding tank to a pneumatic cylinder. The cylinder will be released, hitting and launching a ball into the air. Additionally, force and pressure sensors would allow the energy to be calculated to fully understand the energy transformation. Our priorities for this design …

Mems 411: Vehicle Entry Aid, Sara Wargo, Joshua Doro, Benjamin Swonger, Justin Stohlman

Mechanical Engineering Design Project Class

Handicapped individuals such as those with prosthetic legs or diabetes can struggle greatly with entering large vehicles such as trucks. In this struggle, a client uses a rigid step stool with a rope tied through it to lift himself and then the stool into the vehicle. This report outlines an initiative to design and manufacture a better solution to this problem. A collapsible, two-step step stool was fabricated with a spring loaded retraction system. The design process for this solution is outline from start to finish, showing the extensive thought process that was followed to create the final product.

Mems 411: Asme Design Challenge Hitting Apparatus, Benjamin Deobald, Curtis Hung, Joseph Kodsi, Andrew Sheen

Mechanical Engineering Design Project Class

Develop a specialized hitting mechanism for the modified 2023 ASME Design Competition's mini-golf robot challenge. The mechanism needs to accurately chip and putt golf balls, ensuring compatibility for mounting onto another team's vehicle chassis. Key considerations include weight, form-factor, remote operation ease, and endurance within a $400 budget. The mechanism must adhere to competition rules, stopping before hitting, non-operation during ball contact except for relocation, and transport of the ball to designated areas.

Mems 411: Pinskee Ball - A Work-Energy Demo, Kyle Puckett, Helena Teixeira-Dasilva, Seth Kleinberg, Sydney Norstad

Mechanical Engineering Design Project Class

The goal of our project is to develop a fun and engaging Work-Energy Demo for Dr. James Potter of Washington University in St. Louis and a Science Center or Children's Museum. We aim to teach 6 - 10 year old children about Work-Energy and Energy Transfer in a fun, engaging, and competitive way by using an arcade style machine. The following project is intended to be a Pinball-Based Conservation of Energy Demo/Game for a Science Museum. Using both pinball and skeeball characteristics, this device will give kids thorough knowledge of work energy systems in a fun and interactive way. The …

Mems 411: B2 Striker Group Final Design Report, Jacob Rapoza, Ian M. Veserra, Alex J. Webert, Keaton Porch

Mechanical Engineering Design Project Class

Design a golf striker that can accomplish all the holes set forth by the ASME 2023 design competition and could be attached to a robot without major design modifications.

Mems 411: Heavy Cart Ramp Assistant, Caelyn Walton-Macaulay, Eniya Jaber, Nashleen Salazar Rodriguez

Mechanical Engineering Design Project Class

Some experiments in Prof. Kathy Flores’s lab use argon gas, which is stored in a
big tank. A scale is used to determine how much gas is left in the tank.
To get the tank onto the scale, a person must roll it up a short, fairly steep ramp
onto the scale platform. There is a ramp on the other side of the scale too, so
overshooting the platform causes the ramp to crash into the wall (the lab has taped a foam bumper onto the wall to mitigate this). Once finished, the cart is rolled
back down the ramp, …

Mems 411: 3d Clay Printer, Nanami Mezaki, Isabelle Sasser, Garrett Radtke, Juliana Bush

Mechanical Engineering Design Project Class

The Washington University School of Architecture has a class called Digital Ceramics, that utilizes a 3D Printer that prints clay instead of plastic filament. Students use this device to make art projects. As interesting as this device is, it isn’t without problems. Our team decided to tackle some of the problems involved which we recognized to be: long set-up and tear-down times, and unsuccessful prints due to nozzle falling out.

Mems 411: Dialysqueeze, Ranch Kimball, Maeve Lomax, Tyler Carlson

Mechanical Engineering Design Project Class

Design a device to reduce occupational fatigue injuries suffered by nurses who must manually clamp and unclamp tubing for dialysis machines. This device was designed for MEMS 411 Senior Design.

Mems 411: Bamboo Clamping Device, Grace Chen, Anya Gupta, Yosef Weiss

Mechanical Engineering Design Project Class

The objective of this design project was to create an automatic clamping machine to
keep bamboo bundles tight during lashing. Currently, manual clamping and lashing
of bamboo require simultaneous user effort, posing challenges in terms of efficiency
and safety. Our project introduces a mechanical and automatic clamping tool,
designed to significantly alleviate the physical strain on users and enhance overall
safety. This report details two primary designs of solutions to this problem. The
first is a motor-tightened hose clamp controlled via a three-way switch. The second
design is a claw clamp with an inflatable pouch used to pin the bamboo …

Mems 411: Robot Mini Golf - Striker, Jasmine Davy, Maya Charak, Ilias Bouchibti

Mechanical Engineering Design Project Class

The goal of this project was to design a remote-controlled device that is able to putt and chip a golf ball to achieve several obstacles. This project was designed using the guidelines for the ASME design challenge. The guidelines for this challenge required that the striker fit in a half-meter box, have the capacity to both putt and chip a ball, and be able to overcome obstacles, such as getting up a half pipe onto an elevated surface, clear a 3” hoop, and traverse an inclined ramp. These guidelines had to be met while maintaining a budget of $400.

Mems 411: Mini-Golf Robot Vehicle, Catherine Huang, Shicheng Li, Colin Chen, Maximilian Li

Mechanical Engineering Design Project Class

The primary objective of the project is to develop a remote-controlled vehicle capable of completing a round of mini golf as part of the ASME Student Design Competition. The vehicle’s functionalities are categorized into driving and golf-ball striking. Our group is specifically responsible for the former aspect.

The remote-controlled vehicle is expected to traverse through the designated competition field and exhibit the ability to maneuver between and over obstacles, including a high wall and a low platform. Our design should adhere to the competition regulations set forth by ASME SDC, which include specific criteria for the vehicle such as size …

Mems 411: Motorized Striker, Joseph Crossin, Joana Hadzhilazova, Connor Petersen, Vyas Venkataraman

Mechanical Engineering Design Project Class

This report follows the design and prototyping process for Group B5’s Senior Mechanical Engineering Design Project. Group B5 was tasked with designing a motorized golf striker to perform in the ASME design challenge. This report lays out the progression of the design process beginning with Problem Understanding, then Concept Generation, Concept Selection, Concept Embodiment, Design Refinement, and concludes with an assessment of the final prototype.

Mems 411: Pinch Clamp Clipper, Mackenzie Molina, Jaimie Lin, Oliver Avery

Mechanical Engineering Design Project Class

The purpose of this project was to design a device to take stress off the CMC thumb joint when applying pinch clamps to dialysis tubing. The motivation was to reduce the risk of osteoarthritis in renal care nurses. Sydney Livermore, an OT student at McMaster University, identified that nurses who had to routinely clip pinch clamps on dialysis tubes were at risk of developing osteoarthritis in their CMC joints. She asked us to design a device that could clip the pinch clamps while reducing the force required to do so. The device needed to be able to clip the clamps …

Mems 411: Medical Clamp, Edis Skampo, Rodery Gonzalez, Sokcheatra Samrith, Sean Lucas

Mechanical Engineering Design Project Class

The goal of the team was to design a plier that would be able to clamp down a medical clamp used for a dialysis machine. Ideally the plier should be able to clamp down 3 medical clamps on three separate dialysis tubes in less than 5 seconds, reduce the force required to clamp those clamps by 4 times, and weigh less than 113 grams. The product design was broken down into 3 separate concepts, with four options for each component. The most preferable option of each component was chosen and several risk factors were taken in consideration so that the …

Mems 411: In-Beach Pressure Sampler Design Report, Alex Mccormick, Mark Lipkin, Nirvan Patel Masini, Austin Bick

Mechanical Engineering Design Project Class

Claudio would like a device to put into the beach sand, around nest-depth, to
measure and record data that can determine pressure as waves crash and recede.