Mechanical Engineering Commons^™

Additive Manufacturing Of Stretchable Strain Sensors: Fabrication, Optimization And Application, John Nady Shihat Bastawrous

Theses and Dissertations

In this project, a novel strain sensor design is fabricated employing different additive manufacturing techniques. The spring sensor's primary material is PLA-Like resin with a nanocomposite encapsulation layer as the functional material. The main principle of Straining the sensors results in a change in resistivity as the distances among the conductive carbon particles change according to the strain applied.

Sensor fabrication consists of two parts: spring manufacturing and development of nanocomposite encapsulation The nanocomposite matrix is developed through the dispersion of Graphene and Carbon nanotubes in Thermoplastic Polyurethane through sonication and magnetic hotplate stirring. While the spring itself is manufactured …

Investigation Of Magnetic Bistability For A Wider Bandwidth In Vibro-Impact Triboelectric Energy Harvesters, Qais Qaseem

Mechanical Engineering Theses

Mechanical energy from vibrations is widespread in the ambient environment. It may be harvested efficiently using triboelectric generators. Nevertheless, the harvesters' effectiveness is restricted because of the limited bandwidth. This thesis proposed a comprehensive theoretical and experimental investigation of a variable frequency energy harvester, which integrates a Vibro-impact triboelectric-based harvester and magnetic nonlinearity to increase the operation bandwidth and improve the efficiency of conventional triboelectric harvesters. A cantilever beam with a tip magnet is aligned with another fixed magnet at the same polarity to induce a nonlinear magnetic repulsive force. A triboelectric harvester is integrated into the system by utilizing …

Convexity Applications In Single And Multi-Agent Control, Olli Nikodeemus Jansson

All Graduate Theses and Dissertations

The focus of this dissertation is in the application of convexity for control problems; specifically, single-agent problems with linear or nonlinear dynamics and multi-agent problems with linear dynamics. A mixture of convex and non-convex constraints for optimal control problems is also considered. The main contributions of this dissertation include: 1) a convexification of single-agent problems with linear dynamics and annular control constraint, 2) a technique for controlling bounded nonlinear single-agent systems, and 3) a technique for solving multi-agent pursuit-evasion games with linear dynamics and convex control and state constraints. The first result shows that for annularly constrained linear systems, controllability …

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 …

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

All Graduate Theses and Dissertations

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 …

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 …

Risk Analaysis Of Ethanol Blending Fuel In Refinery Industry Using Event Tree Analysis And Topsis Method, Dinesh Kumar S, Lenin N

International Journal of Mechanical and Industrial Engineering

Chemicals have always posed risks including fire, explosion, and the release of harmful substances in process industries like the Petroleum Industry. The occurrence of such catastrophes has a significant impact on the resources for finances and daily living. In this research paper, the major safety-related causes and effects are identified through event tree analysis based on accidents and incidents while using ethanol as fuel. For this purpose, the accident and incident data collected so far while using ethanol in the fuel industry, detailed information about ethanol, and even tree analysis. The event tree analysis (ETA) and Technique for Order Preference …

Ergonomic Risk Assessment Of Maintenance Workers In Educational Institute, S Lokeeshvar, Surrya Prakash D

International Journal of Mechanical and Industrial Engineering

Risks associated with ergonomics are pervasive groups that have crept into people's daily lives. Ergonomic risks have been linked to long-term health effects like musculoskeletal disorders, cumulative trauma disorders, and lower back pain. Due to the limitations of their jobs, workers are most impacted by these repetitive, continuous labor activities. The main objective of this project is to provide a solution to the ergonomic problems that construction workers in the educational maintenance industry encounter. Based on the conditions, only a few jobs were identified, and samples were obtained by watching and asking people about their jobs. For tasks like plantation, …

Itw Zip-Pak Automatic Splice And Cut Machine, Dylan Miller, Jon Bodine, John Rienow

Scholar Week 2016 - present

Automatic Cut and splice machine to improve the safety and other aspects of ITW Zip-Pak

Presentation in Reed 214

Experimental And Numerical Studies Of Slurry-Based Coextrusion Deposition Of Continuous Carbon Fiber Micro-Batteries To Additively Manufacture 3d Structural Battery Composites, Aditya R. Thakur, Xiangyang Dong

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Carbon Fiber Structural Battery Composites Have Recently Attracted Growing Interests Due to their Potentials of Simultaneously Carrying Mechanical Loads and Storing Electrical Energy for Lightweight Application. in This Study, We Present a Slurry-Based Coextrusion Deposition Method to Additively Manufacture 3D Structural Battery Composites from Carbon Fiber Micro-Batteries. Cathode Slurry is Coextruded Together with Solid Polymer Electrolyte-Coated Carbon Fibers in a Single Deposition. a Network of Carbon Fiber Micro-Batteries is Achieved within the Fabricated Structural Battery Composites. Electrochemical Tests Show a Stable Charge-Discharge Performance Up to 100 Cycles. the Rheological Behavior of the Cathode Slurry is Found to Govern the Coextrusion …

Experimental Evaluations Of The Impact Of An Additive Oxidizing Electronic Air Cleaner On Particles And Gases, Yicheng Zeng, Aurélie Laguerre, Elliott T. Gall, Mohammad Heidarinejad, Brent Stephens

Mechanical and Materials Engineering Faculty Publications and Presentations

Electronic air cleaning (EAC) technologies have garnered significant attention for use in buildings. Many EAC technologies rely on the addition of reactive constituents to indoor air to react with gas-phase compounds, enhance particle deposition, and/or inactivate microorganisms. However, limited data are available on the efficacy of many EAC technologies and their potential to form chemical byproducts during operation. Here we experimentally evaluate the indoor air quality impacts, specifically targeting particles and gases but not microbial constituents, of a commercially available additive oxidizing EAC that generates positive and negative ions and hydrogen peroxide (H2O2). Tests were conducted in a large unoccupied …

Copyright, 3d Printing, And The Value Of Open Vetted 3d Oer, Wilhelmina Randtke, Lee Bareford, John Schlipp

All Things Open

Libraries are protected from copyright lawsuits when patrons make copies, as long as signage is posted and patrons make the copies themselves. But, unlike copying or printing in libraries, self-service 3D printing in libraries is unrealistic. 3D prints take hours to finish, and troubleshooting 3D printing problems takes skill and experience. Meanwhile, the top websites for finding CAD designs to download and 3D print are rampant with copyright infringement. This presentation provides an overview of the status of copyright for 3D printing, covers the tech of why 3D printing is different from printing and copying on paper, and advocates for …

Test 2240: Kubota M8-231, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Thermal Transport Across 2d/3d Van Der Waals Interfaces

Doctoral Dissertations

Designing improved field-effect-transistors (FETs) that are mass-producible and meet the fabrication standards set by legacy silicon CMOS manufacturing is required for pushing the microelectronics industry into further enhanced technological generations. Historically, the downscaling of feature sizes in FETs has enabled improved performance, reduced power consumption, and increased packing density in microelectronics for several decades. However, many are claiming Moore's law no longer applies as the era of silicon CMOS scaling potentially nears its end with designs approaching fundamental atomic-scale limits -- that is, the few- to sub-nanometer range. Ultrathin two-dimensional (2D) materials present a new paradigm of materials science and …

Wind-Wave Misalignment Effects On Multiline Anchor Systems For Floating Offshore Wind Turbines, Doron T. Rose

Masters Theses

Multiline anchors are a novel way to reduce the cost of arrays of floating offshore wind turbines (FOWTs), but their behavior is not yet fully understood. Through metocean characterization and dynamic simulations, this thesis investigates the effects of wind-wave misalignment on multiline anchor systems. Four coastal U.S. sites are characterized in order to develop IEC design load cases (DLCs) and analyze real-world misaligned conditions. Stonewall Bank, Oregon showed the highest 500-year extreme wave height, at 16.6 m, while Virginia Beach, Virginia showed the highest 500-year wind speed, at 56.8 m/s. Misalignment probability distributions, at all sites, are found to converge …

Large Eddy Simulation For Empirical Modeling Of The Wake Of Three Urban Air Mobility Vehicles, Denis-Gabriel Caprace, Andrew Ning

Faculty Publications

Recent advances in urban air mobility have driven the development of many new VTOL concepts. These vehicles often feature original designs departing from the conventional helicopter configuration. Due to their novelty, the characteristics of the super-vortices forming in the wake of such aircraft are unknown. However, these vortices may endanger any other vehicle evolving in their close proximity, owing to potentially large induced velocities. Therefore, improved knowledge about the wakes of VTOL vehicles is needed to guarantee safe urban air mobility operations. In this work, we study the wake of three VTOL aircraft in cruise by means of large eddy …

Optimization Of Acrylonitrile Butadiene Styrene Filament 3d Printing Process Parameters Based On Mechanical Test, Raja S, Rajeswari N

International Journal of Mechanical and Industrial Engineering

This research paper's main goal is to improve the printing parameters that can be used in the 3D Printing Material Extrusion production method in order to get the best printing parameters for Acrylonitrile Butadiene Styrene (ABS) filament with the tensile test in the shortest possible time. The printing parameters that can be employed on 3D printing material extrusion machines include the extruder temperature, layer height, printing speed, and shell count. Also, tensile specimens in accordance with the ASTM (American Society for Testing and Materials) D638 standard were created utilizing ABS filament and the aforementioned adjusted printing settings. The most effective …

An Experimental Investigation Of Multi-Cylinder Conventional Ci Engine Using Madhuca Indica Oil As Fuel, Sreenivas S, Balakrishnan N, Kannan T K, Solaimuthu C

International Journal of Mechanical and Industrial Engineering

The present work is mainly discussed with a qualitative study of engine’s significant characteristics fuelled with mahua bio-diesel & its different types of mixtures with neat diesel. The significant technical properties of various mixtures are tabulated. A 4-S multi-cylinder (6-Cylinder) DI conventional CI engine is used for the study under different speed modes. All types of characteristics for various mixtures are estimated in running the engine. Pure diesel is indicated by B-0 and pure mahua bio-diesel is represented by B-100. From the test results, it is found that B-25 gives almost the same BTE as B-0 at maximum load, compared …

An Experiment To Analyze The Impact Of Steam On The Productivity Of The Rf Stalam 85 Kw Yarn Dryer, Hemanth Kumar Jawahar

International Journal of Mechanical and Industrial Engineering

Radio Frequency has been one of the most commonly used technologies in the processing industries like textile, rubber, paper and many other industries for drying purposes. The RF STALAM 85kW is a machine used to dry the yarn obtained after the dyeing and hydro extraction process. This machine uses radio frequency to remove the moisture content from the dyed yarn. In this research paper, I would like to share the findings of an experiment conducted on the RF STALAM 85kW yarn dryer machine. In this experiment, I have three trials each with and without the steam at variable conveyor belt …

Simulating Steam Jets Due To Rapid Plate Tectonics: A Computational Fluid Dynamics Analysis, Emilie Hatton

Senior Honors Theses

According to the Bible's account of earth's physical history, the majority of geological change from creation to the Ice Age is a consequence of the global Flood cataclysm described in Genesis 6-8. The changes included large-scale tectonic activity, recycling all pre-Flood ocean floor into the mantle, and generating all present-day igneous ocean floor by seafloor spreading at mid-ocean rift zones. Along the middle of these zones, strips of newly formed seafloor were present near the melting temperature of basaltic magma. Above these strips of extremely hot rock, intense jets of steam would almost certainly form. This research seeks to investigate …