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Full-Text Articles in Mechanical Engineering

Evolution Of A Digital Twin For Wing Assembly By Refill Friction Stir Spot Welding, Johnathon Hunt May 2021

Evolution Of A Digital Twin For Wing Assembly By Refill Friction Stir Spot Welding, Johnathon Hunt

Utah Space Grant Consortium

Refill Friction Stir Spot Welding (RFSSW) is an emerging solid state joining process for thin sheet aluminum. Many researchers are developing RFSSW process parameters and best practices for manufacturing, thus enabling the use of RFSSW in many industries. Within this development, this work focuses to predict the resultant residual stresses and distortion in a joined part after welding. These residual stresses are caused by the heat & mechanical inputs from the RFSSW process. This report provides the preliminary results of the two step solution to resultant temperature and stresses from a series of RFSSW in thin sheet aluminum.


Evaluation Of Liquid Doping Methods For Use In Laser Powder Bed Fusion, Taylor Davis May 2021

Evaluation Of Liquid Doping Methods For Use In Laser Powder Bed Fusion, Taylor Davis

Utah Space Grant Consortium

Laser powder bed fusion (LPBF) is an additive manufacturing (AM) process that is well known for its geometric versatility and high-quality parts. While the properties of LPBF parts are commonly superior to those made using other AM techniques, LPBF is generally limited to a single material in any given build. While LPBF can accommodate the integration of multiple components into a single part geometrically, the material limitation leads to over-designing to ensure that every component can complete their various functions. Some studies have shown potential methods of 3D composition control throughout a part, but these methods are subject to high …


Reliable Mode Tracking In Gradient-Based Optimization Frameworks With Flutter Constraints, Taylor Mcdonnell May 2021

Reliable Mode Tracking In Gradient-Based Optimization Frameworks With Flutter Constraints, Taylor Mcdonnell

Utah Space Grant Consortium

In this paper a new mode tracking method is presented which incorporates backtracking logic to maintain a high degree of confidence in mode tracking results. The effectiveness of this mode tracking method is demonstrated on linear and nonlinear aeroelastic systems of varying complexity in the context of aeroelastic analyses and optimizations with stability constraints. The high degree of confidence in mode correlations provided by the new mode tracking method allows for the creation and use of mode-specific C1 continuous stability constraints in gradient-based optimization frameworks. Using our mode tracking method in the context of a gradient-based optimization framework with …


Passive Atmospheric Safety Feature For Small Molten Salt Reactors In Accident Conditions, Brent Edgerton May 2021

Passive Atmospheric Safety Feature For Small Molten Salt Reactors In Accident Conditions, Brent Edgerton

Utah Space Grant Consortium

This investigation aims to discover the utility of atmospheric cooling of residual heat in Martian applications (1.5 MWt). It also considers the possible terrestrial application (45 MWt) of these concepts. The peculiarities of atmospheric cooling require novel geometric arrangements and material selection. The average convection coefficient is derived and applied to ANSYS Transient Thermal analysis for both terrestrial and Martian environments. This preliminary analysis found that atmospheric cooling is a viable method of Martian passive cooling and may serve as a possible method in terrestrial conditions. The key finding of this investigation is that the …


Wake Expansion Continuation: Multi-Modality Reduction In The Wind Farm Layout Optimization Problem, Jared J. Thomas May 2021

Wake Expansion Continuation: Multi-Modality Reduction In The Wind Farm Layout Optimization Problem, Jared J. Thomas

Utah Space Grant Consortium

In this paper we present a continuation optimization method for reducing multi-modality in the wind farm layout optimization problem that we call Wake Expansion Continuation (WEC). We achieve the reduction in multi-modality by starting with an increased wake diameter while maintaining normal velocity deficits at the center of the wakes, and then reducing the wake diameter for each of a series of optimization runs until the accurate wake diameter is used. We applied and demonstrated the effectiveness of WEC with two different wake models. We tested WEC on four optimization case studies with a gradient-based optimization method and a gradient-free …


Miniature Multi-Sensor Array (Mini-Msa) For Ground-To-Stratosphere Air Measurement, Phase Ii, Zachary Kennedy, Drew Huber, Huiling Renee Xie May 2021

Miniature Multi-Sensor Array (Mini-Msa) For Ground-To-Stratosphere Air Measurement, Phase Ii, Zachary Kennedy, Drew Huber, Huiling Renee Xie

Utah Space Grant Consortium

There are numerous college research groups doing high altitude ballooning and working with drones. Many of these are making air quality measurements. Those measurements are effectively random. We are designing an inexpensive and easy to build assembly that others can build for under $500 with the goal of having a uniform data set that can be compared. This will provide more useful data for atmospheric studies. Our first version had too many noise issues and the gas sensor signals were unstable. In December 2020 Winsen Sensors (China) came out with a “multi-in-one sensor module,” the ZPHS01B. At a price point …


Simulated And Phantom Detection Of Microscopic Targets By Raman Spectroscopy, Jordyn Hales May 2021

Simulated And Phantom Detection Of Microscopic Targets By Raman Spectroscopy, Jordyn Hales

Utah Space Grant Consortium

The goal of this study is to determine the minimum spatial sampling resolution required to accurately detect microscopic targets within a sample using Raman spectroscopy. The resolution depends on the light scattering properties of the material. We use Monte Carlo simulations to study how measurement geometry and optical properties of a sample affect the Raman signal detected from an embedded target. We confirm these results using polystyrene beads embedded in artificial tissue phantoms.


Identifying Carbon Structure Via Raman Spectroscopy, Nathaniel Bunker May 2021

Identifying Carbon Structure Via Raman Spectroscopy, Nathaniel Bunker

Utah Space Grant Consortium

  • Raman Spectroscopy: a method to determine molecular composition.
  • Graphene: a conductive, strong, and lightweight material.
  • Our Setup: meant for examining biological samples, not optimized for graphene analysis.


Byu 2021 High Power Rocketry Team, Ryan Thibaudeau, Ryan Merrell May 2021

Byu 2021 High Power Rocketry Team, Ryan Thibaudeau, Ryan Merrell

Utah Space Grant Consortium

Project Objective

Design, build and test a high-power rocket that is capable of carrying a 4 kg payload to 10,000 feet AGL with a commercial motor with less than 40,960 N-S of impulse.

Project Background

The BYU Rocketry Association competes annually in the Spaceport America Cup's International Rocket Engineering Competition. Previous rockets have flown to within 500 feet of the target with a variety of payloads.


Mapping Relative Sand Abundance, Ice-Rich Regions, And Linear Dune Properties Of Titan, Ben Lake, Delaney Rose May 2021

Mapping Relative Sand Abundance, Ice-Rich Regions, And Linear Dune Properties Of Titan, Ben Lake, Delaney Rose

Utah Space Grant Consortium

The equatorial regions of Titan are dominated by linear dune fields made of complex organic particles [1, 2] and have many similarities to terrestrial dunes such as those found in the Namib Sand Sea [1, 3]. Previous studies of Titan’s sand seas included mapping sand sea margins [4, 5, 6, 7] and some dune tracing, but did not involve mapping relative sand abundances. Our work involves mapping relative sand abundances coupled with relative abundances of water ice, as well as more detailed mapping of linear dune morphology.


Lunar Mining: Designing A Versatile Robotic Mining System, James Ehlers, Alexander Charters, Joshua Miraglia, Rian Simpson May 2021

Lunar Mining: Designing A Versatile Robotic Mining System, James Ehlers, Alexander Charters, Joshua Miraglia, Rian Simpson

Utah Space Grant Consortium

The annual NASA Robotic Mining Challenge: Lunabotics tasks teams with building robots capable of traversing and mining in a simulated Lunar terrain. The competition goal is to utilize automation and sensing alongside mechanical systems to harvest icy regolith (simulated with gravel) from beneath the satellite’s surface.


A Preliminary Approach To Select An Origami Source Pattern For Deployable Space Arrays, Diana S. Bolanos May 2021

A Preliminary Approach To Select An Origami Source Pattern For Deployable Space Arrays, Diana S. Bolanos

Utah Space Grant Consortium

This paper presents a systematic approach for selecting an origami pattern for deployable space array applications. A wide variety of origami patterns exist, thereby introducing a daunting task to decide on which pattern is most suitable for the application at hand. Similarly, different space missions present varying requirements. The focus of this paper is to provide aerospace engineers and designers with a framework for identifying optimal origami source models for space array applications.


Assessing Thickness Accommodation Techniques For Deployable Hexagonal Origami Space Arrays, Collin Ynchausti May 2021

Assessing Thickness Accommodation Techniques For Deployable Hexagonal Origami Space Arrays, Collin Ynchausti

Utah Space Grant Consortium

Origami-based and origami-inspired designs provide paths to achieve highly compact, stowable designs, that can be deployed to large surface areas. This potential is highly beneficial to the area of space antennas and LIDAR as these require compact stowing in a launch payload, but large apertures when deployed in space. Because the engineering materials used to build these antennas are thick, thickness accommodation techniques must be applied to realize the same folding motions as the zero-thickness models. This paper presents a hexagonal twist origami pattern in thick materials using three different thickness accommodation techniques. These techniques are compared. The metrics used …


Electromagnetic 3d Printing For Responsive Architectures With An Orthogonal Magnetic Field, Brian Elder May 2021

Electromagnetic 3d Printing For Responsive Architectures With An Orthogonal Magnetic Field, Brian Elder

Utah Space Grant Consortium

The integration of nanomaterials with 3D printing can enable the creation of responsive architecture with highly tunable functional properties. Magnetic nanopatterning is attractive for its ability to produce untethered, high energy density actuation with a broad range of applications. For example, biocompatible materials (such as silicone rubber) can be programmed in an extrusion-based 3D printing process to create a responsive medical soft robot structure.


Defect Detection Limits For Additively Manufactured Parts Using Current Thermography Techniques, Nicholas J. Wallace May 2021

Defect Detection Limits For Additively Manufactured Parts Using Current Thermography Techniques, Nicholas J. Wallace

Utah Space Grant Consortium

Additive manufacturing (AM) will support NASA in their moon and mars missions by reducing the amount of redundant equipment carried into space and by providing crew members with the flexibility to design and create parts as needed. The ability to monitor the quality of these additively manufactured parts is critical, especially when using recycled or in-situ materials as NASA plans to do. This project assesses the possibility of detecting small, shallow AM defects with existing active thermography techniques. An axisymmetric, numerical model was created in COMSOL to simulate the heat transfer within AM structures during active thermography. The effects of …


Aerodynamic Interactions Of Synchronized Propellers, Nathan Welker May 2021

Aerodynamic Interactions Of Synchronized Propellers, Nathan Welker

Utah Space Grant Consortium

Emerging advances in electric-propulsion technology are enabling aircraft to use distributed electric propulsion (DEP) to increase efficiency and maneuverability. Distributed electric propulsion can also provide unique take-off and landing abilities which are not commonly found on traditional aircraft. The implementation of DEP effectively decreases the spacing between propellers, introducing complex aerodynamic interactions that are not well understood. This study aims to obtain experimental measurements of the flow fields of synchronized propellers at close-proximity in a side-by-side configuration using both 2D particle image velocimetry (PIV) and 3D stereoscopic PIV (SPIV) in a wind tunnel. The results of this work will be …


Effect Of Superhydrophobic Surface Microstructure On Transient Jet Impingement Cooling, D. Jacob Butterfield, John Morris May 2020

Effect Of Superhydrophobic Surface Microstructure On Transient Jet Impingement Cooling, D. Jacob Butterfield, John Morris

Utah Space Grant Consortium

Jet impingement is an effective method of rapid surface cooling, and is highly dependent on surface condition and properties. Here, silicon surfaces are modified by ion-etching different micropatterns (posts or holes) on one side and coated with Teflon to make them superhydrophobic (SH). The other side of the surface has a screen-printed resistance heater. Surfaces are heated to temperatures between 200 to 320 °C, and then impinged on by a pure water jet at room temperature with flow rates ranging from 6 to 18 mL/s. Results show that there is little effect of microstructure, although hole surfaces and shorter microstructures …


Assessing The Impact Of Drop Velocity And Spacing In Binder Jetting To Improve Printing In Novel Powders And New Environments, Trenton Colton May 2020

Assessing The Impact Of Drop Velocity And Spacing In Binder Jetting To Improve Printing In Novel Powders And New Environments, Trenton Colton

Utah Space Grant Consortium

Binder Jetting (BJ) is a low-cost Additive Manufacturing (AM) process that uses inkjet technology to selectively bind particles in a powder bed. The interaction of the binder droplets with the powder is essential to the process. This is a complex interaction in which picoliter-sized droplets impact powder beds at velocities of approximately 10 m/s. The binder partially fills the voids between the powders. The fraction of void space filled with binder is the saturation and is a key parameter in BJ. The effects of printing parameters such as droplet velocity, size, and spacing on saturation levels are unknown. This study …


An Examination Into The Defining Characteristics Of Flexible Solar Aircraft Configurations Through Optimization, Taylor Mcdonnell May 2020

An Examination Into The Defining Characteristics Of Flexible Solar Aircraft Configurations Through Optimization, Taylor Mcdonnell

Utah Space Grant Consortium

This paper examines the defining characteristics of various solar aircraft configurations through gradient-based multidisciplinary design optimization. We first present a general gradient-based solar aircraft optimization framework which accounts for nonlinear aeroelastic effects resulting from structural flexibility. We then apply this framework to several discrete SR-HALE aircraft geometric, structural, and propulsion system configuration choices to determine the defining characteristics of each configuration choice.


Comparison Of Wake Expansion Methods For Use In Wake Expansion Continuation Optimization, Jared J. Thomas May 2020

Comparison Of Wake Expansion Methods For Use In Wake Expansion Continuation Optimization, Jared J. Thomas

Utah Space Grant Consortium

This paper presents a comparison of three methods for expanding the wake for use with wake expansion continuation (WEC) optimization. A process related to continuation optimization methods for reducing multi-modality in the wind farm layout optimization problem. A reduction in multi-modality is achieved by starting with an increased wake spread, while maintaining normal velocity deficits at the center of the wakes, and then reducing the wake spread for each of a series of optimization runs until the standard wake spread is used. Three wake expansion methods were tested: (1) increasing the wake expansion angle, (2) multiplying the wake diameter, and …


Model Reference Predictive Adaptive Control For Large Scale Soft Robots, Phillip Hyatt, Curtis Johnson May 2020

Model Reference Predictive Adaptive Control For Large Scale Soft Robots, Phillip Hyatt, Curtis Johnson

Utah Space Grant Consortium

Past work has shown Model Predictive Control (MPC) to be an effective strategy for controlling continuum joint soft robots using rudimentary models, however the in-accuracies of these models often mean that an integration scheme must be combined with MPC. Presented in this work is a novel dynamic model formulation for continuum joint soft robots which is more accurate than the authors’ previous models yet remains fast enough for MPC. This model is based on the Piecewise Constant Curvature (PCC) assumption and a relatively new configuration representation and allows for computationally efficient simulation. Due to the difficulty in determining model parameters …


Influence Of Electrode Height On Carbon Nanotube Electrochemical Biosensors, Benjamin J. Brownlee May 2020

Influence Of Electrode Height On Carbon Nanotube Electrochemical Biosensors, Benjamin J. Brownlee

Utah Space Grant Consortium

High sensitivity of electrochemical sensors enables the detection of low concentrations of target analyte. Being able to quickly and accurately detect low concentrations of proteins at point-of-care allows for results to be analyzed more easily and effectively. Having high surface area allows for more analyte to be detected, possibly leading to increased sensitivity. Vertically-aligned carbon nanotubes (VACNTs) were patterned into interdigitated electrodes (IDEs) and then functionalized with the representative protein streptavidin to demonstrate sensing of biotin. Three electrode heights were investigated to determine the influence of electrode height on sensor sensitivity. Cyclic voltammetry and electrochemical impedance spectroscopy were used to …


Evolutionary Nonlinear Model Predictive Control On A Fixed-Wing And Multirotor, Jaron Ellingson, Matthew Haskell May 2020

Evolutionary Nonlinear Model Predictive Control On A Fixed-Wing And Multirotor, Jaron Ellingson, Matthew Haskell

Utah Space Grant Consortium

Real-time model predictive control (MPC) is limited to short time horizons and linear systems because the optimization complexity is too large with long time horizons and nonlinear systems. For this reason, MPC is typically accomplished using linearized models and convex optimization solvers. We seek to explore evolutionary algorithms allowing for nonlinear models and constraints, non-convex costs, and extended time horizons.

Our contributions include extending nonlinear evolutionary MPC to flight vehicles, fixed-wing and multirotor UAVs, as well as enhancing the evolutionary algorithm. We also intend to parameterize the design space of the optimization to reduce solve times. These contributions validate the …


Aerodynamic Interactions Of Synchronized Propellers, Nathan Welker, Samuel Johnson May 2020

Aerodynamic Interactions Of Synchronized Propellers, Nathan Welker, Samuel Johnson

Utah Space Grant Consortium

Emerging advances in electric-propulsion technology are enabling aircraft to use distributed electric propulsion (DEP) to increase efficiency and maneuverability. Distributed electric propulsion can also provide unique take-off and landing abilities which are not commonly found on traditional aircraft. The implementation of DEP effectively decreases the spacing between propellers, introducing complex aerodynamic interactions that are not well understood. This study aims to obtain experimental measurements of the flow fields of synchronized propellers at close-proximity in a side-by-side configuration using particle image velocimetry (PIV) in a wind tunnel. The results of this work will be focused on identifying the impact closely-spaced propellers …


Monte-Carlo Methods And The Step-Back Kalman Filter For Orbital State Estimation, Louis Tonc May 2020

Monte-Carlo Methods And The Step-Back Kalman Filter For Orbital State Estimation, Louis Tonc

Utah Space Grant Consortium

This research assesses the performance of filtering schemes for tracking uncooperative satellites through space-based optical measurements, and identifies a simple and numerically stable methodology that ameliorates the poor performance of standard filtering schemes at a substantially reduced cost in comparison to nonlinear particle filter-based remedies. Traditional filtering schemes, such as the extended Kalman filter (EKF) and unscented Kalman filter (UKF), both diverge when tracking a resident space object (RSO) in geosynchronous orbit (GEO) when there is a long time duration between measurements. This divergence is identified as a consequence of nonlinearity in the dynamics and nonlinearity in the optical measurements, …


Ensuring Extramobile And Intramobile Motion On Cylindrical Developable Mechanisms, Jared Butler May 2020

Ensuring Extramobile And Intramobile Motion On Cylindrical Developable Mechanisms, Jared Butler

Utah Space Grant Consortium

Developable mechanisms offer the ability to deploy to perform tasks then return to a hidden position along or interior to a predetermined developable surface. It is often advantageous for these mechanisms to not penetrate the surface along which they conform. This paper presents the limits of extramobile and intramobile motion (motion exterior to and interior to a developable surface). Three conditions are identified that determine a limit of extramobile and intramobile behavior. It is shown that the more difficult of these conditions to predict is never reached prior to the more simple cases. This is demonstrated for all possible Grashof …


Gas Gap Conductance Between Ht9 And Ss316, Michael Luke Scoggins, Chris Martinez Apr 2016

Gas Gap Conductance Between Ht9 And Ss316, Michael Luke Scoggins, Chris Martinez

Student Research Symposium

Inside a nuclear reactor, it is important to understand in detail the heat transfer between surfaces. This research aims to ensure the safety of new fuel experiments in the Idaho National Laboratory test reactor by studying the thermal properties of stainless steel and high temperature steel surfaces with a microscopic gas gap between them. The complex behavior of the gas requires a combination of experimental and theoretical modeling. A technique called laser flash analysis is being applied to calculate the effective thermal conductivity of the metal-gas-metal composite sample. From there, gap conductance is calculated using the other known physical parameters …


Monte Carlo Uncertainty Analysis For Photothermal Radiometry Measurements Using A Curve Fit Process, Kyle Horne, Austin Fleming, Heng Ban May 2013

Monte Carlo Uncertainty Analysis For Photothermal Radiometry Measurements Using A Curve Fit Process, Kyle Horne, Austin Fleming, Heng Ban

Utah Space Grant Consortium

Photothermal Radiometry (PTR) has become a popular method to measure thermal properties of layered materials. Much research has been done to determine the capabilities of PTR, but with little uncertainty analysis. This study performs a Monte Carlo uncertainty analysis to quantify uncertainty of film diffusivity and effusivity measurements, presents a sensitivity study for each input parameter, compares linear and logarithmic spacing of data points on frequency scans, and investigates the validity of a 1-D heat transfer assumption.


A One-Dimensional Finite-Difference Solver For Fully-Developed Pipe And Channel Flows, Doug F. Hunsaker May 2010

A One-Dimensional Finite-Difference Solver For Fully-Developed Pipe And Channel Flows, Doug F. Hunsaker

Utah Space Grant Consortium

An algorithm is developed to solve the fundamental flow cases of fully-developed turbulent flow in a pipe and in a channel. The algorithm uses second-order finite-difference approximations for nonuniform grid spacing and is developed in such a way as to easily facilitate the implementation of several two-equation, Reynolds-Averaged-Navier-Stokes turbulence models. Results are included for the Wilcox 1998 k-ω model.