Mechanical Engineering Commons^™

Coordinated, Multi-Arm Manipulation With Soft Robots, Dustan Paul Kraus

Theses and Dissertations

Soft lightweight robots provide an inherently safe solution to using robots in unmodeled environments by maintaining safety without increasing cost through expensive sensors. Unfortunately, many practical problems still need to be addressed before soft robots can become useful in real world tasks. Unlike traditional robots, soft robot geometry is not constant but can change with deflation and reinflation. Small errors in a robot's kinematic model can result in large errors in pose estimation of the end effector. This error, coupled with the inherent compliance of soft robots and the difficulty of soft robot joint angle sensing, makes it very challenging …

Deep Rc: Enabling Remote Control Through Deep Learning, Jaron Ellingson, Gary Ellingson, Tim Mclain

Student Works

Human remote-control (RC) pilots have the ability to perceive the position and orientation of an aircraft using only third-person-perspective visual sensing. While novice pilots often struggle when learning to control RC aircraft, they can sense the orientation of the aircraft with relative ease. In this paper, we hypothesize and demonstrate that deep learning methods can be used to mimic the human ability to perceive the orientation of an aircraft from monocular imagery.

This work uses a neural network to directly sense the aircraft attitude. The network is combined with more conventional image processing methods for visual tracking of the aircraft. …

Secondary Atomization During Droplet Impingement Of Water-Glycerol Admixtures On Heated Superhydrophobic Surfaces, Alexander White, Dr. Julie Crockett

Journal of Undergraduate Research

The purpose of the given document is to remind the reader of goals initially set in conjunction with the ORCA Grant project proposal in October 2016, to present experimental findings obtained during the grant period, and to discuss the results of the work and their implications for future investigations. As stated in the proposal, the main purpose of this ORCA project was to compare the droplet atomization (expulsion of a fine spray) of various water-glycerol mixtures upon impact on superheated, superhydrophobic surfaces. The major goal to that end was to use a certain unique experimental procedure in quantifying the data …

Functional Optimization Of Carbon Nanotubes, Taylor Davis, Sr. Brian Iverson

Journal of Undergraduate Research

The objective of this project was to create, characterize, and optimize carbon nanotube (CNT) films as a surface functionalization strategy through modifying the growth, infiltration, and patterning during fabrication.

Carbon nanotubes have drawn attention in various disciplines in the scientific community because of their incredible strength, hardness, wettability (hydrophobicity), as well as their kinetic and electrical properties. At BYU specifically, they are being used in diverse applications including fabrication of superhydrophobic surfaces and interdigitated electrode biosensors.

Carbon nanotubes can be delicate with a diameter of only a few nanometers when grown. However, the process of carbon infiltration can be used …

Sunflowers, Solar Panels, And Beeswax: Improving Solar Power For The Developing World, Ivyann Oveson Running, Dr. John Salmon

Journal of Undergraduate Research

Inspired by the mechanics of how sunflowers follow the sun, we designed a system to increase output from solar panels by only using simple mechanics and beeswax. Solar power is becoming increasingly popular even in developing countries. We wanted to create a way to increase the power output of solar panels in such areas that lack technical support for current panel rotating mechanisms. When temperatures increase, beeswax expands, and we harness the motion by filling a piston with the beeswax. We use this motion to cause solar panels to turn, following the sun throughout the day and increasing electrical output.

Estimating Joint Configuration For Soft Robots, Jacob Olson, Dr. Marc Killpack

Journal of Undergraduate Research

Soft robotics are still a relatively new technology. As seen in Figure 1, they are made entirely from compliant materials that use pressurized fluid for both structure and actuation. These robots have great potential in the world of robotics. Soft robots can excel in many areas where rigid robots fall short due to their incredible compliance and low inertia. As soft robotic technologies develop, robots will be much less limited in the scope of what they can do without risk of human injury. They will be able to do tasks working more closely with humans in current industries, and be …

Static And Dynamic Obstacle Avoidance For Small Uav, Michael Farrell, Dr. Tim Mclain

Journal of Undergraduate Research

Unmanned aerial vehicles (UAV) are becoming increasingly prevalent in society today. One of the most important problems for such vehicles is obstacle avoidance. Common applications for small UAV require them to navigate through an environment containing many obstacles, both static and dynamic. As part of the 2017 SUAS-AUVSI undergraduate competition, this common problem was simulated with several virtual stationary and moving objects that were to be avoided during flight. The purpose of this research project was to develop a robust obstacle avoidance algorithm to be demonstrated during the mission demonstration of the 2017 SUAS-AUVSI competition.

Refining Statistical Magnesium Models Via Machine Learning, Andrew Orme, Dr. David Fullwood

Journal of Undergraduate Research

Magnesium is a potential replacement for steels and aluminum in strength applications. Despite desirable strength and weight properties, magnesium is costly to manufacture. To reduce manufacturing costs, extensive research has been done on is a phenomenon called twinning, where a large group of magnesium atoms collectively reorient from a base orientation to a new orientation. This reorientation caused by twinning has the potential to enable easier material deformation, allowing for less costly manufacturing. Our research group pursued a novel approach to twinning research by using data mining and machine learning algorithms. Data collected from samples of magnesium using a scanning …

Rigidly Foldable Origami Flashers Based On Curved-Fold Model, Jacob Badger, Dr. Larry Howell

Journal of Undergraduate Research

The purpose of my research was to explore the application of curved folding in designing rigid-foldable deployable mechanisms. In recent years, origami fold patterns known as “flashers” have been investigated for their ability to efficiently pack deployable surfaces. While many patterns have been investigated, none are capable of folding surfaces composed of rigid panels that bend only along crease lines. We hoped to identify one such rigid-foldable flasher by basing it on a curved-fold pattern known as a logarithmic spiral flasher.

Above Knee Prosthetic Socket For Developing Countries, Colton Graham, Dr. Mark Colton

Journal of Undergraduate Research

Due to a civil war in Sierra Leone many have been left with amputated limbs. In order to provide the required prosthetic limbs for victims who have above the knee amputations they need a quality custom fit socket. Custom fit sockets are very expensive so we created a universal socket meant to comfortably fit everyone. This socket is also designed to be affordable and able to be manufactured in Sierra Leone. For a functional socket, it is to be custom fitted, durable, affordable, adjustable and comfortable for the amputee. Due to varying changes to the volume of the residual limb, …

Carbon Nanotube Filtration Device: Separating Oil From Fracking Waste, Phillip Ng, Dr. Anton Bowden

Journal of Undergraduate Research

Pyrolytic Carbon Infiltration Carbon Nanotubes (CI-CNTs) can isolate water and oil molecules due to its superhydrophobic and oleophilic properties, unique cylindrical nanostructure, and functional groups¹. Because the waste produced from fracking is nonreusable due to the molecular oil droplets contained in it, the waste is typically injected back underground, which pollutes safe drinking water². This can be avoided with an inexpensive and efficient oil and water filter. The mentored research project revolved around a CI-CNT filter used to salvage waste created from fracking.

The design of a CI-CNT device was approached by three main considerations: a …

Gas Detection System For Biomass Cookstove Emissions, Cyra Bishop, Jeffery Smith, Dr. Matthew Jones

Journal of Undergraduate Research

The purpose of this research project is to explore Peruvian social and cultural behaviors that typically prevent successful improved cookstove adoption in resource-limited settings as well as suggest ways to educate locals about the benefits of improved cookstoves. This will be done by constructing a cost-effective, easy-to-use gas-detection sensor system capable of measuring concentrations of harmful gases released from biomass cookstoves typically found in Peruvian communities.

Modeling Vocal Fold Intravascular Flow With Synthetic Replicas, Aaron David Terry

Theses and Dissertations

Communication by voice is foundational in our society and many rely on their voices for their occupations. Voice disorders affect a significant number of individuals each year, and diagnosis and treatment improvements are therefore sought via advancements in voice research. Contained in this thesis is a description of work intended to contribute to vocal fold research by using synthetic, self-oscillating vocal fold replicas to study the impact of replica vibration on perfusion fluid flow through the replica. Methods for manufacturing vocal fold replicas containing imbedded channels allowing for fluid perfusion are discussed. Experimental procedures developed for delivering perfusion fluid to …

Thermal Transport At Superhydrophobic Surfaces In Impinging Liquid Jets, Natural Convection, And Pool Boiling, Matthew Clark Searle

Theses and Dissertations

This dissertation focuses on the effects of superhydrophobic (SHPo) surfaces on thermal transport. The work is divided into two main categories: thermal transport without phase change and thermal transport with phase change. Thermal transport without phase change is the topic of four stand-alone chapters. Three address jet impingement at SHPo surfaces and the fourth considers natural convection at a vertical, SHPo wall. Thermal transport with phase change is the topic of a single stand-alone chapter exploring pool boiling at SHPo surfaces. Two chapters examining jet impingement present analytical models for thermal transport; one considered an isothermal wall and the other …

Visual Servoing For Multirotor Precision Landing In Varying Light Conditions, Jesse Wynn, Tim Mclain

Faculty Publications

The problem of performing a precision landing of an autonomous multirotor UAV in various lighting conditions is studied. A vision-based approach is proposed and consists of varying degree-of-freedom image-based visual servoing (VDOF-IBVS), and a specialized landing marker. The proposed approach is validated through extensive flight testing outdoors in both lighted and dark conditions, and is done using a standard off-the-shelf autopilot system.

Developable Compliant-Aided Rolling-Contact Mechanisms, Todd G. Nelson, Just L. Herder

Student Works

Rolling-contact mechanisms can provide low-friction motion with unique kinematic paths. We show that developable surfaces can be used as a design tool for rolling-contact mechanisms joined with compliant bands. These mechanisms can exhibit 3D motion paths, couple rotational and translational motions into a single degree of freedom, and can be designed to exhibit various tailored kinetic responses. We set forth developable surface parametrizations well suited to the creation of rolling contacts. We highlight how the geodesic and principal curvatures of the non-ruling principal curves of a developable surface are meaningful design quantities for rolling contacts. We provide kinematic and kinetic …

Experimental And Theoretical Investigation Of Mechanical Response Of Laser-Sintered Diamond Lattice Structures, Clayton Neff, Neil Hopkinson, Nathan B. Crane

Faculty Publications

Typically additive manufacturing (AM) processes are limited to a single material per part while many products benefit from the integration of multiple materials with varied properties. To achieve the benefits of multiple materials, the geometric freedom of AM could be used to build internal structures that emulate a range of different material properties such as stiffness, Poisson’s ratio, and elastic limit using only one build material. This paper examines the range of properties that can be simulated using diamond lattice structures manufactured from Nylon 12 with a commercial laser sintering process. Diamond lattices were fabricated with a unit cell length …

Total Hemispherical Apparent Radiative Properties Of The Infinite V-Groove With Diffuse Reflection, Rydge B. Mulford, Nathan S. Collins, Michael S. Farnsworth, Matthew R. Jones, Brian D. Iverson

Faculty Publications

DYNAMIC control of radiative surface properties enables optimization of thermal management systems for spacecraft, radiative cooling systems, and other applications [1–3]. Various methods of altering the absorption or emission from a surface have been investigated [4–6]. Use of origami-inspired tessellated surfaces to control apparent radiative surface properties is a promising technology [7–9]. Realizing the full potential of tessellated surfaces to dynamically control apparent radiative surface properties requires convenient methods of calculating apparent properties as a function of tessellation geometry and intrinsic radiative surface properties. This Note focuses on the use of geometry to affect total, hemispherical properties of V grooves …

Impact Of Extended Sintering Times On Mechanical Properties In Pa-12 Parts Produced By Powderbed Fusion Processes, Garrett Craft, Justin Nussbaum, Nathan B. Crane, J. P. Harmon

Faculty Publications

Additive Manufacturing provides many advantages in reduced lead times and increased geometric freedom compared to traditional manufacturing methods, but material properties are often reduced. This paper considers powder bed fusion of polyamide 12 (PA12, Nylon 12) produced by three different processes: laser sintering (LS), multijet fusion (MJF)/high speed sintering (HSS), and large area projection sintering (LAPS). While all utilize similar PA12 materials, they are found to differ significantly in mechanical properties especially in elongation to break. The slower heating methods (MJF/HSS and LAPS) produce large elongation at break with the LAPS process showing 10x elongation and MJF/HSS exhibiting 2.5x the …

Methods And Metrics To Measure And Predict The Social Impact Of Engineered Products, Phillip Douglas Stevenson

Theses and Dissertations

More than ever before, engineers are creating products for developing countries. One of the purposes of these products is to improve the consumer's quality of life. Currently, there is no established method of measuring the social impact of these types of products. As a result, engineers have used their own metrics to assess their product's impact, if at all. Some of the common metrics used include products sold and revenue, which measure the financial success of a product without recognizing the social successes or failures it might have. In this thesis I introduce a potential metric, the Product Impact Metric …

Efficient Incorporation Of Fatigue Damage Constraints In Wind Turbine Blade Optimization, Bryce Taylor Ingersoll

Theses and Dissertations

Improving the wind turbine blade design has a significant effect on the efficiency of the wind turbine. This is a challenging multi-disciplinary optimization problem. During the blade design process, the aerodynamic shapes, sizing of the structural members, and material composition must all be determined and optimized. Some previous blade design methods incorporate the wind turbine's static response with an added safety factor to account for neglected dynamic effects. Others incorporate the dynamic response, but in general is limited to a few design cases. By not fully incorporating the dynamic response of the wind turbine, the final turbine blade design is …

Electrochemical Glucose Sensors Enhanced By Methyl Viologen And Vertically Aligned Carbon Nanotube Channels, Benjamin J. Brownlee, Meisam Bahari, John H. Harb, Jonathan C. Claussen, Brian D. Iverson

Faculty Publications

Free-standing, vertically aligned carbon nanotubes (VACNTs) were patterned into 16 μm diameter microchannel arrays for flow-through electrochemical glucose sensing. Non-enzymatic sensing of glucose was achieved by the chemical reaction of glucose with methyl viologen (MV) at an elevated temperature and pH (0.1 M NaOH), followed by the electrochemical reaction of reduced-MV with the VACNT surface. The MV sensor required no functionalization (including no metal) and was able to produce on average 3.4 electrons per glucose molecule. The current density of the MV sensor was linear with both flow rate and glucose concentration. Challenges with interference chemicals were mitigated by operating …

Electrochemical Glucose Sensors Enhanced By Methyl Viologen And Vertically Aligned Carbon Nanotube Channels, Benjamin J. Brownlee, Meisam Bahari, John N. Harb, Jonathan C. Claussen, Brian D. Iverson

Faculty Publications

Freestanding, vertically aligned carbon nanotubes (VACNTs) were patterned into 16 μm diameter microchannel arrays for flow-through electrochemical glucose sensing. Non-enzymatic sensing of glucose was achieved by the chemical reaction of glucose with methyl viologen (MV) at an elevated temperature and pH (0.1 M NaOH), followed by the electrochemical reaction of reduced-MV with the VACNT surface. The MV sensor required no functionalization (including no metal) and was able to produce on average 3.4 electrons per glucose molecule. The current density of the MV sensor was linear with both flow rate and glucose concentration. Challenges with interference chemicals were mitigated by operating …

Design For Maintainability In Developing Communities—A Case Study On The Uros Islands, Thomas Barlow

Undergraduate Honors Theses

Designing products for developing communities has exposed many of the underlying assumptions that engineers from developed nations have during the design process. There has been much written about these underlying assumptions in order to create a better framework for designing for developing communities. One unexplored, yet important area is the universality of common maintainability principles used in developed countries when designing products used in developing communities. Such principles include: simplicity, diagnosability, standardization of parts, modular subassemblies, minimizing assembly and disassembly parts, labeling components, increased life of moving parts, manuals, and simplifying tools needed for repairs [1]–[3]. The purpose of this …

Methods For Creating Rigid Foldability In Origami-Inspired Deployable Mechanisms, Alden Daniel Yellowhorse

Theses and Dissertations

Because origami has proved to be a tremendously rich source of inspiration in engineering, interest in solving some of the challenges that affect origami-inspired design has been significant. One such challenge involves ensuring that origami-inspired mechanisms are rigid-foldable or capable of moving without requiring links to bend or distort. Because rigid-foldability is essential in mechanisms that are constructed using rigid materials, access to methods of engineering this characteristic are highly desirable. This research addresses this need by developing methods for the design of origami-inspired mechanisms that are rigid-foldable. Methods for modifying crease patterns to achieve this are described and compared. …

Total Hemispherical Apparent Radiative Properties Of The Infinite V-Groove With Diffuse Reflection, Rydge B. Mulford, Nathan S. Collins, Michael S. Farnsworth, Matthew R. Jones, Brian D. Iverson

Faculty Publications

Dynamic control of radiative surface properties enables optimization of thermal management systems for spacecraft, radiative cooling systems and other applications [1-3]. Various methods of altering the absorption or emission from a surface have been investigated [4-6]. Use of origami-inspired, tessellated surfaces to control apparent radiative surface properties is a promising technology [7-9]. Realizing the full potential of tessellated surfaces to dynamically control apparent radiative surface properties requires convenient methods of calculating apparent properties as a function of tessellation geometry and intrinsic radiative surface properties. This paper focuses on the use of geometry to affect total, hemispherical properties of V-grooves comprised …

Tactile Sensing And Position Estimation Methods For Increased Proprioception Of Soft-Robotic Platforms, Nathan Mcclain Day

Theses and Dissertations

Soft robots have the potential to transform the way robots interact with their environment. This is due to their low inertia and inherent ability to more safely interact with the world without damaging themselves or the people around them. However, existing sensing for soft robots has at least partially limited their ability to control interactions with their environment. Tactile sensors could enable soft robots to sense interaction, but most tactile sensors are made from rigid substrates and are not well suited to applications for soft robots that can deform. In addition, the benefit of being able to cheaply manufacture soft …

Evaluation Of Processing Variables In Polymer Projection Sintering, Justin Nussbaum, Nathan B. Crane

Faculty Publications

Purpose – Projection sintering, a system for selectively sintering large areas of polymer powder simultaneously with a high power projector is introduced. The paper evaluates the suitability of laser sintering process parameters for projection sintering as it uses substantially lower intensities, longer exposure times, and larger areas than conventional laser sintering (LS).

Design/methodology/approach – The tradeoffs in sintering outcomes are evaluated by creating single layer components with varied exposure times and optical intensities. Some of these components were cross-sectioned and evaluated for degree of densification while the single layer thickness and the maximum tensile force was measured for the rest. …

Bubble Nucleation In Superhydrophobic Microchannels Due To Subcritical Heating, Adam Cowley, Daniel Maynes, Julie Crockett, Brian D. Iverson

Faculty Publications

This work experimentally studies the effects of single wall heating on laminar flow in a high-aspect ratio superhydrophobic microchannel. When water that is saturated with air is used as the working liquid, the non-wetted cavities on the superhydrophobic surfaces act as nucleation sites and allow air to effervesce out of the water and onto the surface when heated. Previous works in the literature have only considered the opposite case where the water is undersaturated and absorbs air out the cavities for a microchannel setting. The microchannel considered in this work consists of a rib/cavity structured superhydrophobic surface and a glass …

Universal Airfoil Parametrization Using B-Splines, Dev Rajnarayan, Andrew Ning, Judd Mehr

Faculty Publications

In this paper, we apply well-known techniques for parametric curves to the definition and deformation of airfoil sections. While it has already been shown that many versions of Kulfan’s Class Shape Transformation (CST) are exactly equivalent to Bézier curves, we show here that all NACA 4-digit thickness distributions and the PARSEC parametrization of Sobiezcky are also higher-order Bézier curves. As with CST, Béziers and B-Splines provide direct control over aerodynamically meaningful features such as nose radius and boat-tail angle, but also provide more a intuitive parametrization of the rest of the airfoil surface. We show the efficacy of B-Spline-based parametrizations …