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Mechanical Engineering

2019

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Quantitative Peel Test For Thin Films/Layers Based On A Coupled Parametric And Statistical Study, Maysam Rezaee, Li Chih Tsai, Muhammad Istiaque Haider, Armin Yazdi, Ehsan Sanatizadeh, Nathan P. Salowitz Dec 2019

Quantitative Peel Test For Thin Films/Layers Based On A Coupled Parametric And Statistical Study, Maysam Rezaee, Li Chih Tsai, Muhammad Istiaque Haider, Armin Yazdi, Ehsan Sanatizadeh, Nathan P. Salowitz

Mechanical Engineering Faculty Articles

The adhesion strength of thin films is critical to the durability of micro and nanofabricated devices. However, current testing methods are imprecise and do not produce quantitative results necessary for design specifications. The most common testing methods involve the manual application and removal of unspecified tape. This overcome many of the challenges of connecting to thin films to test their adhesion properties but different tapes, variation in manual application, and poorly controlled removal of tape can result in wide variation in resultant forces. Furthermore, the most common tests result in a qualitative ranking of film survival, not a measurement with ...


Smart Factories, Dumb Policy? Managing Cybersecurity And Data Privacy Risks In The Industrial Internet Of Things, Scott J. Shackelford Dec 2019

Smart Factories, Dumb Policy? Managing Cybersecurity And Data Privacy Risks In The Industrial Internet Of Things, Scott J. Shackelford

Minnesota Journal of Law, Science & Technology

No abstract provided.


Failure Of High Strength Concrete Under Dynamic Uniaxial Compression, Colin Loeffler Dec 2019

Failure Of High Strength Concrete Under Dynamic Uniaxial Compression, Colin Loeffler

Mechanical Engineering Research Theses and Dissertations

The failure strength of concrete materials has been widely shown to be dependent on experimental parameters such as specimen geometry and strain-rate. The effects of specimen geometry have been shown both theoretically and experimentally to be a result of the quasi-brittle nature of concrete. While the failure strength of concrete has been widely reported to increase significantly when deformed at high strain-rates, the physical mechanisms driving this phenomenon remain the source of debate amongst researchers. This means that constitutive models designed to predict this rate dependent behavior are not based on the real physical mechanisms that drive this behavior but ...


Acoustic Design Optimization With Isogeometric Analysis And Differential Evolution, Garrett W. Dodgen Dec 2019

Acoustic Design Optimization With Isogeometric Analysis And Differential Evolution, Garrett W. Dodgen

Mechanical Engineering Theses

The objective of this study is to utilize shape optimization to enhance the performance of devices relying on acoustic wave propagation. Particularly, the shape of a horn speaker and an acoustic energy harvester were optimized to enhance their performance at targeted frequencies. High order Isogeometric Analysis (IGA) was performed to estimate the acoustic pressure with minimum geometry and pollution errors [1]. The analysis platform was then combined with Differential Evolution (DE) to optimize the geometry of the horn speaker and energy harvester at a given frequency. These cases effectively demonstrate two applications of Isogeomtric shape optimization for devices relying on ...


Biomechanical Analysis Of Open-Skull High-Rate Traumatic Brain Injury Using Finite Element Mouse Brain Model, Lihong Lu Dec 2019

Biomechanical Analysis Of Open-Skull High-Rate Traumatic Brain Injury Using Finite Element Mouse Brain Model, Lihong Lu

Electronic Thesis and Dissertation Repository

To better understand traumatic brain injury (TBI), it is necessary to correlate with injuries, which are observed from in vivo laboratory experiments, to brain mechanical responses, which can so far be best predicted by finite element (FE) models. Firstly, a previously validated FE model was improved to investigate the effect of repeated impacts and lateral movements on brain responses to ensure the accuracy and reproducibility of controlled cortical impact (CCI) across different labs. Then, a new FE mouse brain model with the detailed three-dimensional (3D), non-linear vasculature was developed to study how the vasculature affected brain response in CCI and ...


Asme Design Challenge: The Jenga Stacker, Zachary Lin, Alex Chernauskas, Mitch Dorsey, Alex Remmers Dec 2019

Asme Design Challenge: The Jenga Stacker, Zachary Lin, Alex Chernauskas, Mitch Dorsey, Alex Remmers

Mechanical Engineering Design Project Class

The 2020 ASME Design Challenge requires teams to build a compact engineering system capable of manufacturing a tower made exclusively from standard-sized sheets of paper. The validation of the design will include testing for manufacturing speed, height of tower, and ability to support a load. Our senior design project focuses on the stacking mechanism and is designed to stack a 4 in x 4 in tower out of prepared 4 in x 1.5 in x 1.75 in paper boxes from the ground up.


Group A: Asme Student Design Challenge, Dakshi Jindal, Ashley Perry, Ben Liao Dec 2019

Group A: Asme Student Design Challenge, Dakshi Jindal, Ashley Perry, Ben Liao

Mechanical Engineering Design Project Class

This year's student design competition is termed "Building to the Sky." Student teams are required to build a compact engineering system capable of manufacturing a tower made of only standard-sized sheets of paper.


Group S- Arliss Project, Preston Bailey, Zach Stelwagon, Cal Reynolds, James Hardy Dec 2019

Group S- Arliss Project, Preston Bailey, Zach Stelwagon, Cal Reynolds, James Hardy

Mechanical Engineering Design Project Class

Our project was the ARLISS competition project, more specifically the second part of the project where the vehicle must survive a drop and drive to a known location over rough desert terrain. We interviewed our professor, Dr. Potter, who had previous experience with the project to understand what was required in our design. The project started with creating concept ideas and deciding on one, which initially was an airplane to avoid designing a landing mechanism and having to drive over rough terrain. However, this design proved to have too many flaws and was scrapped. The new design was a small ...


Integrated Design Approach For Coronary Stents Using Flexinol Shape Memory Alloy, Matthew Lucci Dec 2019

Integrated Design Approach For Coronary Stents Using Flexinol Shape Memory Alloy, Matthew Lucci

Mechanical Engineering Theses

This research seeks to develop and verify a model for control of the shape memory alloy (SMA) Flexinol and apply such findings to practical application of the material as a platform for bare metal stenting technologies. Utilizing experimental data and material properties, a mathematical model of the thermoelectric contraction behavior of Flexinol wire samples was developed. This model accounted for variable resistance due to the shape memory effect of the Flexinol wire as it experiences a crystalline phase change. It also accounted for the change in the cross-sectional area of the wire as the wire experienced thermal expansion and contraction ...


Mems 411 Group L (Fall 2019) - Speedy Seeder Final Report, Michael Morrow, Christopher Nelson, Ross Frame Dec 2019

Mems 411 Group L (Fall 2019) - Speedy Seeder Final Report, Michael Morrow, Christopher Nelson, Ross Frame

Mechanical Engineering Design Project Class

The Speedy Seeder or ”SS” is a device designed to decrease the time it takes to fill one seed plot by hand to roughly sixteen percent of the time. The customer of the SS is EarthDance Organic Farms School. EarthDance fills a large number of plots each year by placing a seed in every single compartment which come in three sizes: 32, 72, and 128 compartments per plot. Filling a single plot by hand can take roughly 8 minutes. The SS makes filling a plot much easier and faster, allowing a single plot to be filled in under 75 seconds ...


3d Chocolate Printer Bed Design, Dean Oken, Jacob Margolin, Ben Hartmann, Sam Grossman Dec 2019

3d Chocolate Printer Bed Design, Dean Oken, Jacob Margolin, Ben Hartmann, Sam Grossman

Mechanical Engineering Design Project Class

The client wished for a device to gain the interest of young undergraduate students into basic thermal science and fluid dynamics concepts. A 3D printer bed was created from concept to prototype design and paired with chocolate dropper teams to complete the project and accomplish the client's goals.


Energy Modelling To Evaluate The Thermal Regulation Of Aquaculture Raceways Using Geothermal Heat Exchange, Mitchell H. Kuska Dec 2019

Energy Modelling To Evaluate The Thermal Regulation Of Aquaculture Raceways Using Geothermal Heat Exchange, Mitchell H. Kuska

Electronic Thesis and Dissertation Repository

Raceways are used in the aquaculture industry to farm fish species that swim against an upstream current. Raceways often draw water from a large waterbody and hence, their temperature changes due to seasonal variation, which directly affect the production yield. This study investigates a novel approach to regulate the raceway water temperature in a sustainable way by utilizing geothermal energy exchange. Energy models were developed to simulate heat transfer in a geothermal borehole heat exchange system and in the raceway system. The two models were then coupled to simulate the thermal regulation of the raceway water via borehole heat exchangers ...


T-Shirt Strip Dispenser, Maxwell Dimgba, Syeda Mohsin, Sabrina Nguyen Dec 2019

T-Shirt Strip Dispenser, Maxwell Dimgba, Syeda Mohsin, Sabrina Nguyen

Mechanical Engineering Design Project Class

There is a massive amount of waste around the textile industry. New garments are constantly being made and old garments are consistently finding themselves in landfills. This project aims to cut down on this waste. Mary Susan RuppertStroescu of the Sam Fox School at Washington University in St. Louis has developed a process to turn old garments into new ones in a practice known as up-cycling. By cutting old garments into half-inch strips, laying and adhering them flat on a sheet of dissolvable paper, and sewing over them in interesting patterns she is able to create extraordinary new designs. This ...


Violin Bow-Hand Prosthetic, Ron Hayes Jr, Kc Cook, Romario Lobban, Muriel Drexler Dec 2019

Violin Bow-Hand Prosthetic, Ron Hayes Jr, Kc Cook, Romario Lobban, Muriel Drexler

Mechanical Engineering Design Project Class

The violin bow-hand prosthetic aims to mimic the natural hold and motion of a violinist’s bow-hand. The prosthetic is for a violinist who is missing the majority of their hand, but still has full range of motion in the wrist. Focusing on maintaining a natural playing style greatly influenced the design of the device to be user safe, durable, comfortable, easy to use, inexpensive, and practical. Many of these features were achieved by using 3D printed plastic and foam composites. These materials were selected based on strength and deflection analyses of 3-D simulations performed in SolidWorks and the ease ...


Violin Bow-Hand Prosthetic, Jonathan Smith, Jonathon Azziz, Shawn Pavey Dec 2019

Violin Bow-Hand Prosthetic, Jonathan Smith, Jonathon Azziz, Shawn Pavey

Mechanical Engineering Design Project Class

The violin bow hand prosthetic was designed for a young violin player seeking to upgrade the functionality of his current violin prosthetic device. His current device is rigid, forcing him to play mostly with his shoulder. Since the strength of his wrist was unknown, we designed a prosthetic with enough brace flexibility to enable the user to control the bow motion with his own wrist. We also added an axis of rotation and spring mechanism to supplement this motion and provide him the equivalence of fine finger adjustments. The full design process of the prosthetic is documented in this report ...


Group M: Arliss Canister Vehicle, Greyson Bourgeois, Eleanor Macklin, Romail Dawani, Rachel Sample Dec 2019

Group M: Arliss Canister Vehicle, Greyson Bourgeois, Eleanor Macklin, Romail Dawani, Rachel Sample

Mechanical Engineering Design Project Class

This project is a dicycle designed for the ARLISS Canister Competition. In this competition, the device is loaded into a rocket which is then launched to about 12000 ft before releasing the device. Then it must safely land and autonomously navigate to a predetermined GPS location on the ground. Due to the fact that this is a mechanical engineering design project and the time restrictions of this class, we focused on the physical aspect of the project, such as building a device that can survive the launch and landing and traverse several kilometers through the desert, forgoing the autonomous navigation ...


Energy Performance Certification: Misassessment Due To Assuming Default Heat Losses, Ciara Ahern, Brian Norton Dec 2019

Energy Performance Certification: Misassessment Due To Assuming Default Heat Losses, Ciara Ahern, Brian Norton

Articles

Energy Performance Certificates (EPCs) are issued when dwellings are constructed, sold or leased in the EU. Where the cost of obtaining the required data is prohibitive, EPC assessors use nationally applicable default-values. To ensure that dwellings are not assigned a wrongly-higher EPC rating, a standardised thermal bridging transmittance coefficient (Y-value) is typically adopted for all existing dwellings while worst-case overall heat loss coefficients (U-values) are used. Default U-values are applied to a specific building element type (roof, wall, floor etc.) based on building codes and regulations applicable at time of construction. Due to significant building fabric upgrades, default U-values are ...


Lupd - Leisure Underwater Propulsion Device, James Abraham, Tanner Nordell, Holden Schmidt, Noah Trimark Dec 2019

Lupd - Leisure Underwater Propulsion Device, James Abraham, Tanner Nordell, Holden Schmidt, Noah Trimark

Mechanical Engineering Design Project Class

The main objective of this Design Project was to create a hands-free, wearable underwater propulsion device. The target consumer is leisure divers, so managing cost was important. Current products on the market do not allow divers to be hands-free while diving and are very expensive. The design process began with an interview with Josh An, a Masters Degree candidate at Washington University in St. Louis. Josh is an avid diver and wanted to see if it was possible to develop a cheap underwater jet pack for leisure diving. After multiple design concepts and mock up prototypes, our team decided on ...


Cdse Quantum Dots Synthesis Laboratory Course For High School Students, Danlin Zuo, Gyuseok Kim, David Jones Dec 2019

Cdse Quantum Dots Synthesis Laboratory Course For High School Students, Danlin Zuo, Gyuseok Kim, David Jones

Protocols and Reports

Cadmium selenide quantum dot is a fascinating subject for leading high school students to the quantum world. An 8-hour laboratory course for up to 12 high school students is proposed. The 8-hour course consist of two 4-hours sections. This laboratory course includes the quantum dot syntheses, absorption and emission characterization, and data analysis. The proposes process runs at relatively lower temperature which means safe and easy, and shows apparent experimental results.


Sweet Spot Demonstration, Andrew Amend, Mitchell Smith, Ian Fish, Curtis Hoffman Dec 2019

Sweet Spot Demonstration, Andrew Amend, Mitchell Smith, Ian Fish, Curtis Hoffman

Mechanical Engineering Design Project Class

Our goal was to design and build an exhibit for the St. Louis Science Center to serve as a teaching tool to help explain the unintuitive concept of a baseball bat’s sweet spot to a typical children museum’s visitor, a 5th grade student, in an interesting and visually pleasing way. The sweet spot of the bat is colloquially known as the place that makes the best contact with the ball, and it is determined by a combination of the center of percussion and location of vibrational nodes. We focused on showing how the location of bat-ball impact affects ...


Automated Whiteboard Eraser, Trent Houpt, Tyler Polasek, Kenny Huang, Rocky Luo Dec 2019

Automated Whiteboard Eraser, Trent Houpt, Tyler Polasek, Kenny Huang, Rocky Luo

Mechanical Engineering Design Project Class

The Automated Whiteboard Eraser is a product designed to erase whiteboards with the touch of a button. With this product students and teachers will be able to save time and energy as they can continue to work without having to stop and erase. From our research others have attempted to construct similar products. We intend to improve these thoughts and designs in order to build a better and more efficient product.


Violin Prosthetic, Justin Kransdorf, Julia Rifkin, Hayden Reynolds, Payal Hukeri Dec 2019

Violin Prosthetic, Justin Kransdorf, Julia Rifkin, Hayden Reynolds, Payal Hukeri

Mechanical Engineering Design Project Class

Sam, an 11-year-old violin player was born without fingers or a thumb on his right hand. In order to learn the basics of violin, he currently uses a custom made prosthetic that allows him to hold a violin bow. However, his current prosthetic does not allow for the bow angle to change relative to his wrist, and thus, he cannot perform many techniques that are important to him furthering his violin skills. Specifically, his prosthetic allows Sam to use only a small percentage of the bow. For this project, a prosthetic was designed for Sam with the goal being to ...


Board Erasing Device, Mark Fernandez, Christopher Sheffels, Joshua Miller Dec 2019

Board Erasing Device, Mark Fernandez, Christopher Sheffels, Joshua Miller

Mechanical Engineering Design Project Class

The Board Erasing Device is a portable automatic device designed to streamline a university lecturer’s board writing process by automatically erasing whiteboards while they are writing notes on adjacent boards. Our goal during this project was to design, build, and test a portable, automatic, and aesthetically pleasing device compatible with most standard whiteboards on Washington University in St. Louis’ Danforth campus. To that end, with a budget of $400, we created a prototype device to accomplish just that. Our prototype includes a felt eraser, pressed into the whiteboard via magnets. The eraser piece spans all eight feet of width ...


Sweet Spot Demonstration, Keval Amin, Beau Allen, Kieran Lenssen, Ricardo Del Olmo Parrado Dec 2019

Sweet Spot Demonstration, Keval Amin, Beau Allen, Kieran Lenssen, Ricardo Del Olmo Parrado

Mechanical Engineering Design Project Class

The purpose of this project was to create a sweet spot exhibit for the St. Louis Science Center to demonstrate the basic dynamic and vibrational theory behind the game of baseball. This demonstration focuses on the dynamics of batting and the effects that induced bat vibrations have on the energy transfer from the bat to the ball. Through this demonstration, the vibrational nodes within a baseball bat can be measured based on the ball’s contact with the ”sweet spot,” or the area on the barrel of the bat that induces the least amount of bat vibration. The project went ...


Ice Cream Dispensing Machine, Katie Bahnck, Rachel Lockwood, Marie White, Simone Raeth Dec 2019

Ice Cream Dispensing Machine, Katie Bahnck, Rachel Lockwood, Marie White, Simone Raeth

Mechanical Engineering Design Project Class

Each August, Washington University in St. Louis (WashU) welcomes hundreds of new engineering students to its McKelvey School of Engineering. Historically, during orientation activities, WashU’s Engineering Student Services (ESS) serves dessert bars to the new students, where they must line up and make their own desserts manually. To make the dessert bar more interactive and give students a primer for what their engineering studies hold, we would like to introduce an ice cream sundae making machine to the spread. A semi-automated ice cream machine would allow students to customize their ice cream sundae while observing the everyday mechanics required ...


Asme 2020 Design Challenge, Anthony Acosta, Justine Alandy-Dy, Michael Lorberg, Nathan Vaska Dec 2019

Asme 2020 Design Challenge, Anthony Acosta, Justine Alandy-Dy, Michael Lorberg, Nathan Vaska

Mechanical Engineering Design Project Class

Our project was to build a machine that would fulfill the requirements for the ASME 2020 design challenge, which was called, ”Building to the Sky.” The rules of the challenge were to build a machine that would take ordinary 8.5” x 11” sheets of paper and stack them into a tower. To accomplish this task, we decided to make our paper tower out of accordion-shaped folds that would be placed on top of each other, alternating in 90 degree orientations. Our device is divided into various sub-components, each which manipulate the paper in various ways. We first have a ...


3d Chocolate Printer Dropper, Jessica Jimenez, Jacqueline Pielli, Shuhan Zhang Dec 2019

3d Chocolate Printer Dropper, Jessica Jimenez, Jacqueline Pielli, Shuhan Zhang

Mechanical Engineering Design Project Class

The Mechanical Engineering Department at Washington University in St. Louis is working to stimulate interest in the fields of fluid dynamics and thermal sciences, as students are not typically exposed to these topics within the first two years of school. Dr. Okamoto, Jeff Krampf, and Dr. Weisensee of the Mechanical Engineering Department would like to remedy this situation by developing a laboratory experiment for first year students that utilizes a 3D chocolate printer to teach thermal-fluid concepts in a fun and engaging manner. The goal of this project is to build a chocolate droplet dispensing system, which is a part ...


Jet Beluga: Diver Propulsion Wearable, Jacob Graham, Bernardo Amaral Neves, Ethan Genter Dec 2019

Jet Beluga: Diver Propulsion Wearable, Jacob Graham, Bernardo Amaral Neves, Ethan Genter

Mechanical Engineering Design Project Class

Scuba diving is a physically and mentally challenging task performed in both recreational and professional settings. Recreational divers seek to experience the marine world for extended periods of time without buoyant resistance. Rescue divers, military personnel, and underwater construction workers train to execute complicated tasks in a limited time period. Diver propulsion vehicles can improve the quality of recreational diving as well as the effectiveness of diving as performed in professional settings. The following report describes the design and motivations for a wearable diver propulsion device that provides the benefits of increased speed and mobility while limiting the amount of ...


A Deep Learning Framework For Design And Analysis Of Surgical Bioprosthetic Heart Valves, Aditya Balu, Sahiti Nallagonda, Fei Xu, Adarsh Krishnamurthy, Ming-Chen Hsu, Soumik Sarkar Dec 2019

A Deep Learning Framework For Design And Analysis Of Surgical Bioprosthetic Heart Valves, Aditya Balu, Sahiti Nallagonda, Fei Xu, Adarsh Krishnamurthy, Ming-Chen Hsu, Soumik Sarkar

Mechanical Engineering Publications

Bioprosthetic heart valves (BHVs) are commonly used as heart valve replacements but they are prone to fatigue failure; estimating their remaining life directly from medical images is difficult. Analyzing the valve performance can provide better guidance for personalized valve design. However, such analyses are often computationally intensive. In this work, we introduce the concept of deep learning (DL) based finite element analysis (DLFEA) to learn the deformation biomechanics of bioprosthetic aortic valves directly from simulations. The proposed DL framework can eliminate the time-consuming biomechanics simulations, while predicting valve deformations with the same fidelity. We present statistical results that demonstrate the ...


A Wearable Mechatronic Device For Hand Tremor Monitoring And Suppression: Development And Evaluation, Yue Zhou Dec 2019

A Wearable Mechatronic Device For Hand Tremor Monitoring And Suppression: Development And Evaluation, Yue Zhou

Electronic Thesis and Dissertation Repository

Tremor, one of the most disabling symptoms of Parkinson's disease (PD), significantly affects the quality of life of the individuals who suffer from it. These people live with difficulties with fine motor tasks, such as eating and writing, and suffer from social embarrassment. Traditional medicines are often ineffective, and surgery is highly invasive and risky. The emergence of wearable technology facilitates an externally worn mechatronic tremor suppression device as a potential alternative approach for tremor management. However, no device has been developed for the suppression of finger tremor that has been validated on a human.

It has been reported ...