Digital Commons Network^™

Developable Mechanisms On Right Conical Surfaces, Lance P. Hyatt, Spencer P. Magleby, Larry L. Howell

Faculty Publications

An approach for designing developable mechanisms on a conical surface is presented. By aligning the joint axes of spherical mechanisms to the ruling lines, the links can be created in a way that the mechanism conforms to a conical surface. Terminology is defined for mechanisms mapped onto a right cone. Models are developed to describe the motion of the mechanism with respect to the apex of the cone, and connections are made to cylindrical developable mechanisms using projected angles. The Loop Sum Method is presented as an approach to determine the geometry of the cone to which a given spherical …

On The Modeling Of A Contact-Aided Cross-Axis Flexural Pivot, Pietro Bilancia, Giovanni Berselli, Spencer P. Magleby, Larry L. Howell

Faculty Publications

This paper reports the study of a planar Cross-Axis Flexural Pivot (CAFP) comprising an additional contact pair. The proposed device turns useful for applications requiring a revolute joint that behaves differently when deflecting clockwise/anti-clockwise. The presence of the contact pair reduces the free length of one flexures, resulting in a considerable increment of the overall joint stiffness. The pivot behaviour is investigated, for different load cases, via the ChainedBeam-Constraint Model (CBCM), namely an accurate method to be applied in large deflection problems. A framework comprising Matlab and ANSYS is developed for testing the CAFP performances in terms of rotational stiffness, …

Sustainably Providing Accurate Local River Discharge Data With Global Hydrologic Modeling And Bias Corrections, Riley Chad Hales

Theses and Dissertations

The Global Water Sustainability Initiative of the Group of Earth Observations (GEOGloWS) supported an initiative to develop a global hydrologic model. The purpose of the modeling initiative is to build a high-quality model using the best available datasets and modeling methods with the primary emphasis on accessibility of the model. The goal is to make the model a sustainable source of river discharge information to supplement the capacity of those countries without the local capacity to maintain sufficient gauge networks and local modeling capabilities and cyberinfrastructure. Past research developed a modeling approach and piloted implementations and data and visualization services …

Heat Set Creases In Polyethylene Terephthalate (Pet) Sheets To Enable Origami-Based Applications, Brandon Sargent, Nathan Brown, Brian D. Jensen, Spencer P. Magleby, William G. Pitt, Larry L. Howell

Faculty Publications

Polyethylene terephthalate (PET) sheets show promise for application in origami-based engineering design. Origami-based engineering provides advantages that are not readily available in traditional engineering design methods. Several processing methods were examined to identify trends and determine the effect of processing of PET sheets on the crease properties of origami mechanisms in PET. Various annealing times, temperatures, and cooling rates were evaluated and data collected for over 1000 samples. It was determined that annealing temperature plays the largest role in crease response. An increase in the crystallinity of a PET sheet while in the folded state likely increases the force response …

An Origami-Based Medical Support System To Mitigate Flexible Shaft Buckling, Brandon Sargent, Jared Butler, Kendall Seymour, David Bailey, Brian D. Jensen, Spencer P. Magleby, Larry L. Howell

Faculty Publications

This paper presents the development of an origami-inspired support system (the OriGuide) that enables the insertion of flexible instruments using medical robots. Varying parameters of a triangulated cylindrical origami pattern were combined to create an effective highly-compressible anti-buckling system that maintains a constant inner diameter for supporting an instrument and a constant outer diameter throughout actuation. The proposed origami pattern is composed of two repeated patterns: a bistable pattern to create support points to mitigate flexible shaft buckling and a monostable pattern to enable axial extension and compression of the support system. The origami-based portion of the device is combined …

Kinetostatic And Dynamic Modeling Of Flexure-Based Compliant Mechanisms: A Survey, Mingxiang Ling, Larry L. Howell, Junyi Cao, Guimin Chen

Faculty Publications

Flexure-based compliant mechanisms are becoming increasingly promising in precision engineering, robotics and other applications due to the excellent advantages of no friction, no backlash, no wear, and minimal requirement of assembly. Because compliant mechanisms have inherent coupling of kinematic- mechanical behaviors with large deflections and/or complex serial-parallel configurations, the kinetostatic and dynamic analyses are challenging in comparison to their rigid-body counterparts. To address these challenges, a variety of techniques have been reported in a growing stream of publications. This paper surveys and compares the conceptual ideas, key advances, applicable scopes and open problems of the state-of-the-art kinetostatic and dynamic modeling …

A Cprbm-Based Method For Large-Deflection Analysis Of Contact-Aided Compliant Mechanisms Considering Beam-To-Beam Contacts, Mohui Jin, Benliang Zhu, Jiasi Mo, Zhou Yang, Xianmin Zhang, Larry L. Howell

Faculty Publications

Contact-aided compliant mechanisms (CCMs) utilize contact to achieve enhanced functionality. The contact phenomenon of CCMs increases the difficulties of their analysis and design, especially when they exhibit beam-to-beam contact. Considering the particularity of CCMs analysis, which is more about the mechanisms’ deformation, this paper presents a numerical method to analyze the large deflection and stress of the CCMs considering beam-to-beam contacts. Based on our previous work on beam-to-rigid contact, the large deformation of general beams in CCMs is modeled by using the chained pseudo-rigid-body model (CPRBM). An approximation based on the geometric information of CPRBM is proposed in this paper …

Design Of Regular 1d, 2d, And 3d Linkage-Based Tessellations, Alden D. Yellowhorse, Nathan Brown, Larry L. Howell

Faculty Publications

Linkage origami is one effective approach for addressing stiffness and accommodating panels of finite size in origami models and tessellations. However, successfully implementing linkage origami in tessellations can be challenging. In this work, multiple theorems are presented that provide criteria for designing origami units or cells that can be assembled into arbitrarily large tessellations. The application of these theorems is demonstrated through examples of tessellations in two and three dimensions.

Deployable Convex Generalized Cylindrical Surfaces Using Torsional Joints, Todd G. Nelson, Jared T. Burton, Curtis G. Nelson, Luis M. Baldelomar Pinto, Zhicheng Deng, Larry L. Howell

Faculty Publications

The ability to deploy a planar surface to a desired convex profile with a simple actuation can enhance foldable or morphing airfoils, deployable antennae and reflectors, and other applications where a specific profile geometry is desired from a planar sheet. A model using a system of rigid links joined by torsional springs of tailorable stiffness is employed to create an approximate curved surface when two opposing tip loads are applied. A system of equations describing the shape of the surface during deployment is developed. The physical implementation of the model uses compliant torsion bars as the torsion springs. A multidimensional …

Membrane-Enhanced Lamina Emergent Torsional Joints For Surrogate Folds, Guimin Chen, Spencer P. Magleby, Larry L. Howell

Faculty Publications

Lamina emergent compliant mechanisms (including origami-adapted compliant mechanisms) are mechanical devices that can be fabricated from a planar material (a lamina) and have motion that emerges out of the fabrication plane. Lamina emergent compliant mechanisms often exhibit undesirable parasitic motions due to the planar fabrication constraint. This work introduces a type of lamina emergent torsion (LET) joint that reduces parasitic motions of lamina emergent mechanisms (LEMs), and presents equations for modeling parasitic motion of LET joints. The membrane joint also makes possible one-way joints that can ensure origami-based mechanisms emerge from their flat state (a change point) into the desired …

Limits Of Extramobile And Intramobile Motion Of Cylindrical Developable Mechanisms, Jared Butler, Larry L. Howell, Spencer P. Magleby, Jacob Greenwood

Faculty Publications

Mechanisms that can both deploy and provide motions to perform desired tasks offer a multifunctional advantage over traditional mechanisms. Developable mechanisms (DMs) are devices capable of conforming to a predetermined developable surface and deploying from that surface to achieve specific motions. This paper builds on the previously identified behaviors of extramobility and intramobility by introducing the terminology of extramobile and intramobile motion, which define the motion of developable mechanisms while interior and exterior to a developable surface. The limits of motion are identified using defined conditions. It is shown that the more difficult of these conditions to kinematically predict may …

Analysis Of The Rigid Motion Of A Conical Developable Mechanism, Mckell Woodland, Michelle Hsiung, Erin L. Matheson, C Alex Safsten, Jacob Greenwood, Denise M. Halverson, Larry L. Howell

Faculty Publications

We demonstrate analytically that it is possible to construct a developable mechanism on a cone that has rigid motion. We solve for the paths of rigid motion and analyze the properties of this motion. In particular, we provide an analytical method for predicting the behavior of the mechanism with respect to the conical surface. Moreover, we observe that the conical developable mechanisms specified in this paper have motion paths that necessarily contain bifurcation points which lead to an unbounded array of motion paths in the parameterization plane.

Load-Displacement Characterization In Three Degrees Of Freedom For General Let Arrays, Nathan A. Pehrson, Pietro Bilancia, Spencer P. Magleby, Larry L. Howell

Faculty Publications

Lamina emergent torsion (LET) joints for use in origami-based applications enables folding of panels. Placing LET joints in series and parallel (formulating LET arrays) opens the design space to provide for tunable stiffness characteristics in other directions while maintaining the ability to fold. Analytical equations characterizing the elastic load-displacement for general serial-parallel formulations of LET arrays for three degrees of freedom are presented: rotation about the desired axis, in-plane rotation, and extension/compression. These equations enable the design of LET arrays for a variety of applications, including origami-based mechanisms. These general equations are verified using finite element analysis and, to show …

Engineering And Characterization Of Antibodies Against Cancer Biomarker Thymidine Kinase 1, Joshua Bennett, Kiara V. Whitley, Christopher J. Haynie, Kim O'Neill

Library/Life Sciences Undergraduate Poster Competition 2023

Engineered antibodies used in immunotherapies have been increasingly successful due to their ability to uniquely target cells expressing specific cancer antigens Thymidine Kinase 1 (TK 1 is a DNA salvage enzyme typically found in the cytosol However, in certain types of cancer, TK 1 is surface expressed, making it a unique cancer biomarker By identifying antibodies with a high binding affinity for TK 1 we can target cancer cells expressing TK 1 on their surface Using cell sorting and a yeast display library expressing 109 human single chain antibody fragments, we have isolated ten unique single chain antibodies scFvs that …

Air Quality: Comparison Of Pm2.5 Levels In Evaporative Vs Central Air Homes In Utah County Using Filter-Based Sampling, Alisandra Olivares, Taylor Christensen, Paula Chanthakhoun, Jim Johnston, Darrell Sonntag

Library/Life Sciences Undergraduate Poster Competition 2023

PM_2.5 is particulate matter that is less than 2.5 micrometers. Combustion of fuels, gas, natural gas, and wood are contributors to the production of PM_2.5.

Employing Echogenicity As A Tool To Predict Injury To Achilles Tendon, Evan Armknecht, Joshua K. Sponbeck, Steven Allen, Shayla Bott, Chris Dillon, Camille Nguyen, Annie Allen, A. Wayne Johnson

Library/Life Sciences Undergraduate Poster Competition 2023

Dance is a common activity that many young women participate in around the world. While there are many beneficial aspects of participating in dance, physical activity in certain genres of dance experience high Achilles tendon loading force, which impact the risk of Achilles tendon injury.

Understanding early biomechanical predictors of tendon injury may prevent debilitating tendon injuries.

Ultrasound imaging allows for detailed analysis of tendon structure, including tendon density and water content (echogenicity).

The purpose of this study is to investigate the effect of pain due to Achilles tendon injury and one biomechanical property of a tendon, echogenicity.

Detecting And Characterizing Multisensory Integrating Optic Tectum Neurons In Zebrafish, Adeline Hamilton, Karianne Jex, Erika C. Marks., Suehelen A. Garcia, Jordan T. Yorgason, Tracianne B. Neilsen, Arminda Suli

Library/Life Sciences Undergraduate Poster Competition 2023

The superior colliculus (SC) is a mammalian midbrain structure involved in multimodal sensory integration and is implicated to have a role in neurodevelopmental disorders. Although the presence of multisensory integrating neurons (MINs) in the SC has been well documented by electrophysiology techniques, little is known about their morphological or molecular characterization. To identify and study MINs, we utilized SC’s non-mammalian homologous structure–the optic tectum (OT)–in the genetically tractable model organism zebrafish. In this process, we generated transgenic lines that allowed for fluorescent detection of neuronal activity by expressing the genetically engineered calcium indicators: cytoRGECO and H2B-jRGECO1a, respectively in mechanosensory hair …

The Effect Of Menstruation Duration On The Achilles Tendon Cross-Sectional Area In Female Ballet Dancers, Li Kaitong, Aaron W. Johnson, Steven Allen, Shayla Bott, Chris Dillon, Joshua K. Sponbeck, Camille Nguyen Jones, Annie Allen

Library/Life Sciences Undergraduate Poster Competition 2023

Females are more likely to suffer Achilles tendon injury that consequently leads to more complications including pain or tendon rupture, and experiencing fewer benefits from therapeutic interventions. There is a lack of knowledge on how estrogen, which may limit collagen synthesis, can affect tendon health and growth. The duration and cross-sectional area (CSA) of the Acobjective of this study is to examine the relationship between menstruation hilles tendon over a 5-month period of intensive dance training.

Designing A Makerspace, Mackenzie Dinsmoor

Instructional Psychology and Technology Graduate Student Projects

The purpose of this project was to design a makerspace in the McKay School of Education here at Brigham Young University. This project is for pre-service teachers and faculty in the Teacher Education Department primarily in the Elementary Education program.

The purpose of a makerspace is to provide students with the materials and experiences to iteratively design and create. It’s a place for hands-on learning with all the tools for creativity. Makerspaces provide creative ways to encourage students to design, experiment, build and invent as they deeply engage in science, engineering and tinkering. A makerspace is not solely a science …

Applied Machine Learning In Development Of Geospatial Information Tools For Sustainable Groundwater Management, Saul Gallegos Ramirez

Theses and Dissertations

Groundwater plays an important role in sustainable water resource management. Globally, the development of groundwater resources for irrigation provides a stable water source and enhances food security. However, developing groundwater resources is difficult, requiring the collection, synthesis, analysis, and dissemination of information about groundwater in an accessible, effective manner so decision makers have the knowledge and tools to implement sustainable management strategies. In this dissertation, I present solutions to assist with the paucity of groundwater data. The first problem I explore is extending the Palmer Drought Severity Index to near present day. This dataset is crucial to current groundwater imputation …

Zero Torque Compliant Mechanisms Employing Pre-Buckled Beams, Pietro Bilancia, Samuel Porter Smith, Giovanni Berselli, Spencer P. Magleby, Larry L. Howell

Faculty Publications

The concept of a statically balanced mechanism with a single rotational degree of freedom is presented. The proposed device achieves static balancing by combining positive stiff- ness elements and negative stiffness elements within a nuclear domain. Two designs are discussed. The first is composed of an Archimedean spiral and two pinned-pinned pre-buckled beams. The overall mechanism is modeled via an analytical approach and the element dimensions are optimized. The optimal configuration is then tested through finite element analysis (FEA). A second approach replaces the spiral beam with elastic custom-shaped spline beams. An FEA optimization is performed to determine the shape …

Conceptualizing Stable States In Origami-Based Devices Using An Energy Visualization Approach, Jacob Greenwood, Larry L. Howell, Alex Avila, Spencer P. Magleby

Faculty Publications

In many origami-based applications, a device needs to be maintained in one or more fold states. The origami stability integration method (OSIM) presented in this paper pro- vides an approach for graphically combining various techniques to achieve stability. Existing stability techniques are also categorized into four groups based on whether they are intrinsic or extrinsic to the origami pattern and whether they exhibit gradual or non-gradual energy storage behaviors. These categorizations can help designers select appropriate techniques for their applications. The paper also contains de- sign considerations and resources for achieving stability. Finally, two case studies are presented that use …

Civilizational Heritage In The Age Of Innovation: Exploring The Importance Of Civilizational Heritage In The 21st Century, Bibi Pelić, Ulrike Michel-Schneider

Comparative Civilizations Review

‘What has civilizational heritage to do with innovation?’ you may ask. ‘I just got the latest iPhone and don’t see any connection.’ You would not be the only one to ask this question.

If we backtrack a thousand years or so and look at innovations from the past, such as the Via Appia or the Colosseum, did the Romans think about civilizational heritage when they built these two magnificent structures? Did they care about civilizational heritage? What about the ancient Egyptians whose building innovation, ‘the pyramid,’ is still an enigma for us today?

Innovation is thus nothing new, but it …

A Comparative Analysis Of Black American Student Experiences And International Student Experiences During The Initial Months Of The Covid-19 Pandemic, Leah P. Hollis Edd

Comparative Civilizations Review

The Covid-19 pandemic created an indelible mark on K-12 education — specifically, high school students transitioning to college and career. The global scope of this pandemic presented an opportunity to compare how high school cultures across the world adapted to the emergency. Further, news reports highlighted how communities of color were more susceptible to the pandemic.

To better understand how the Black student experience in middle America compared to that of other students from the global community in responding to pandemic-related educational disruption, I used Krippendorff’s content analysis procedures (2018) and a phenomenological interview process to gather and analyze data …

Alegaatr The Bandit, Ethan Pedersen

Theses and Dissertations

One design strategy for developing intelligent agents is to create N distinct behaviors. At each time step during task execution, the agent, or bandit, chooses which of the N behaviors to use. Traditional bandit algorithms often (1) assume the environment is stationary, (2) focus on asymptotic performance, and (3) do not incorporate external information available to them. Each of these simplifications limits these algorithms such that they often cannot be used successfully in practice. In this paper, we propose a new algorithm, called AlegAATr, as a step toward overcoming these deficiencies. AlegAATr utilizes a technique called Assumption-Alignment Tracking (AAT), proposed …

Measured Spectral, Directional Radiative Behavior Of Corrugated Surfaces, Kyle S. Meaker, Ehsan Modfidipour, Matthew R. Jones, Brian D. Iverson

Faculty Publications

Spacecraft thermal control is entirely reliant upon radiative heat transfer with its surroundings for tem- perature regulation. Current methods are often static in nature and do not provide dynamic control of radiative heat transfer. As a result, modern spacecraft thermal control systems are typically ‘cold-biased’ with radiators that are larger than necessary for many operating conditions. Deploying a variable radiator as a thermal control technique in which the projected surface area can be adjusted to provide the appro- priate heat loss for a given condition can reduce unnecessary heat rejection and reduce power require- ments. However, the radiative behavior of …

Tracing East Asian Librarianship In Correspondence: A Data Analysis Of Eastlib Messages From 1995 To 2020, Tang Li, Junjiro Nakatomi, Xiang Li

Journal of East Asian Libraries

The Eastlib listserv, established by the Council on East Asian Libraries (CEAL) as its official mailing list in the early 1990s and hosted at the University of North Carolina, Chapel Hill until the end of May 2022, has been the primary communication channel for East Asian librarians in North America for nearly 30 years. In 1999, Eastlib’s functionality was enhanced to allow its subscribers and the general public to browse and search through email discussions online. However, due to unanticipated system setting changes, it was discovered in March 2020 that access to the online Eastlib archive was limited to postings …

Lists Of Selected Full-Text Databases By Subscription In East Asian Studies, Dongyun Ni, Michiko Ito, Ellie Kim, Anlin Yang

Journal of East Asian Libraries

No abstract provided.

Sootlib: A Soot Model Library For Combustion Simulation, Victoria B. Stephens, Joshua Bedwell, Alex J. Josephson, Keturah Oldham, David O. Lignell

Faculty Publications

Soot formation in combustion is an important process that affects radiative heat transfer, flame temperatures, and emissions with health and environmental impacts. Soot formation involves complex chemistry for nucleation, growth, oxidation, and coagulation processes. The soot particles vary widely in size and accurate modeling requires representation of the particle size distribution (PSD). Modeling soot is not trivial, and is only one of several physical processes active in combustion systems. This paper presents a software package called SootLib, which is an open-source library for modeling soot formation and other aerosol systems. SootLib is written in C++, is documented with Doxygen, and …

Effects Of Post-Translational Histone Modifications On Transcription Rate, Aaron Bohn, Sarah Hodson, Sarah Ricks, David Bates Ph.D, Steven M. Johnson Ph.D

Library/Life Sciences Undergraduate Poster Competition 2023

The structural organization of DNA in eukaryotic cells is greatly implicated in the regulation of gene expression and thus cellular properties and behavior. At the most fundamental unit of this organization, ~147 bp of DNA wraps 1.7 times around a histone octamer core, forming a collective unit called the nucleosome. The positioning and occupancy of these nucleosomes around the promoter elements of genes is known to be a strong regulator of transcription in eukaryotic nuclei, and post-translational modifications (PTM’s) to the protruding N-terminal tails of histone proteins are known to influence chromatin structure and thus gene expression; however, relatively little …