Applied Mechanics Commons^™

Application Of Computational Tools To Spaghetti-Based Truss Bridge Design, Jin Xu, Jiliang Li, Nuri Zeytinoglu, Jinyuan Zhai

ASEE IL-IN Section Conference

Application of Computational Tools to Spaghetti-Based Truss Design

Statics and Strength of Materials are two foundational courses for Mechanical/Civil Engineering. In order to assist students in better understanding and applying concepts to a meaningful design task, SolidWorks and theoretical calculation were used for a spaghetti-bridge design contest with the constraints of given maximum weight and allowable support-material weight. As the first step of this iterative designing process, both extrude feature and structural member were introduced to model planar bridge trusses. Then SolidWorks’ Statics module was used to run FEA analysis of the structural performance in efforts to optimize the …

Answering Food Insecurity: Serving The Community With Food And Knowledge Using Technology, Courtney Simpson

Purdue Journal of Service-Learning and International Engagement

The courses of Tech120, CGT110, and ENGT 180/181 and Red Gold at Purdue collaborated to design a robot that would plant and water a garden for a local community charter school. The students centered the project on the users’ needs for fresh food, nutrition education, and early exposure to STEM for children. The school, Anderson Preparatory Academy (APA), is comprised of many children who come from low-income families and are in the free or reduced lunch program. Inspired from “Farm Bot,” a similar system that allows for almost hands-free gardening, the “Boiler Bot” is designed to be scalable so children …

Comparative Analysis Of Impact Attenuation Properties From Soccer Headgear, Kevin G. Mciver, Goutham N. Sankaran, Justin J. Markel, Tom M. Talavage, Larry J. Leverenz, Eric A. Nauman

The Summer Undergraduate Research Fellowship (SURF) Symposium

Athletes suffering from long-term neurocognitive deficiency due to subconcussive impacts is a major concern for football and soccer players today. Football players wear helmets that can help reduce injury risks like skull fractures, and these helmets must meet standard criteria that determinines how well a functional helmet should reduce accelerations of the player’s head. Currently no standard exists for testing soccer headgear despite studies demonstrating soccer players experience similar magnitudes of impacts. In this study, a modal impact hammer was used in conjunction with a Hybrid III 50th percentile test dummy head to simulate impacts experienced by soccer players to …

Development Of Portable Hyperspectral Imaging Device, Chenxi Li, Youngkee Jung, Iyll-Joon Doh, Euiwon Bae

The Summer Undergraduate Research Fellowship (SURF) Symposium

Most of the conventional hyperspectral imaging devices require sophisticated optical components, occupy a large footprint, and requires an initial capital investment for laboratories which mostly suits for laboratories benchtop system. The requirement of shipping the sample and waiting an extended period of time to get the results are the main downsides of this traditional approach. Capitalize in many specific field applications and diagnosis, portable devices provide both convenience and on-site results which are desirable for government agencies and food safety inspectors. This project was aimed to develop a low-cost, portable hyperspectral device for food safety applications. A smartphone was used …

Stability Analysis Of A Flexible Vehicle Model Controlled By Human Pilot Models, Abhishek Ajmani, Anil Bajaj

The Summer Undergraduate Research Fellowship (SURF) Symposium

There is a constant race among automobile manufactures to design safer vehicles while minimizing weight to reduce power consumption. Additionally, organizations like NASA and SpaceX are persistently working toward creating reliable, lightweight rovers to be used on the surface of Mars. However, the lightweight requirement often increases vehicle flexibility, which further develops a tendency toward instability in the lateral (sideways) direction. This investigation develops a mathematical model that represents the dynamics of a flexible vehicle in forward motion, and a heuristic human pilot model is proposed which controls the vehicle. Following such formulation, the combined vehicle and pilot model is …

Mathematical Description And Mechanistic Reasoning: A Pathway Toward Stem Integration, Paul J. Weinberg

Journal of Pre-College Engineering Education Research (J-PEER)

Because reasoning about mechanism is critical to disciplined inquiry in science, technology, engineering, and mathematics (STEM) domains, this study focuses on ways to support the development of this form of reasoning. This study attends to how mechanistic reasoning is constituted through mathematical description. This study draws upon Smith’s (2007) characterization of mathematical description of scientific phenomena as ‘‘bootstrapping,’’ where negotiating the relationship between target phenomena and represented relations is fundamental to learning. In addition, the development of mathematical representation presents a viable pathway towards STEM integration. In this study, participants responded to an assessment of mechanistic reasoning while cognitive interviews …

Modeling And Computation Of The Maximum Braking Energy Speed For Transport Category Airplanes, Nihad E. Daidzic

Journal of Aviation Technology and Engineering

Transport-category or FAR/CS 25 certified airplanes may occasionally become braking energy capacity limited. Such limitation may exist when heavy airplanes are departing airports at high-density altitudes, on relatively long runways, and/or possibly with some tailwind component. A maximum braking energy VMBE speed exists which may limit the maximum allowable takeoff decision/action speed V1. The ever-existing possibility of high-speed rejected takeoff in such conditions may also limit the airplane gross weight for declared available distances. To gain deeper insights and acquire better understanding of the topic, a theoretical model of the maximum braking energy and the related VMBE speed for T-category …

Analysis Of Composite Plates By Using Mechanics Of Structure Genome And Comparison With Ansys, Banghua Zhao

Open Access Theses

Motivated by a recently discovered concept, Structure Genome (SG) which is defined as the smallest mathematical building block of a structure, a new approach named Mechanics of Structure Genome (MSG) to model and analyze composite plates is introduced. MSG is implemented in a general-purpose code named SwiftComp™, which provides the constitutive models needed in structural analysis by homogenization and pointwise local fields by dehomogenization. To improve the user friendliness of SwiftComp™, a simple graphic user interface (GUI) based on ANSYS Mechanical APDL platform, called ANSYS-SwiftComp GUI is developed, which provides a convenient way to create some common SG models or …

A Sharp Interface Isogeometric Strategy For Moving Boundary Problems, Tao Song

Open Access Dissertations

The proposed methodology is first utilized to model stationary and propagating cracks. The crack face is enriched with the Heaviside function which captures the displacement discontinuity. Meanwhile, the crack tips are enriched with asymptotic displacement functions to reproduce the tip singularity. The enriching degrees of freedom associated with the crack tips are chosen as stress intensity factors (SIFs) such that these quantities can be directly extracted from the solution without a-posteriori integral calculation.

As a second application, the Stefan problem is modeled with a hybrid function/derivative enriched interface. Since the interface geometry is explicitly defined, normals and curvatures can be …

Study On The Impact Abrasive Wear Of New Super-High Manganese Steel, Wenyan Wang

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Numerical And Experimental Characterization Of Material Flow In Forged Aluminum Wheel, Jong-Ning Aoh, Ming-Chiu Li, Chong-Jin Li

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Numerical Modeling And Simulation Of Welding Residual Stresses Using Finite Element Method, Jing Zheng, Ayhan Ince

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Modeling On Tail Pinch In Finishing Rolls During Hot Strip Rolling, Jong-Ning Aoh, Han-Kai Hsu, Ming-Fa Chen

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Simulation On The Sealing Of Aluminum Ball Joint, Haobin Tian, Xiaohang Liu, Xuelei Li, Jun Feng

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Research Of The Metal Flow Picture In The Upsetting Based On Computer And Physical Simulation, Konstantin Nikolaevich Solomonov

The 8th International Conference on Physical and Numerical Simulation of Materials Processing

No abstract provided.

Cyclic Tensile Response Of A Polyurethane Material, Yizhou Nie

Open Access Theses

Polyurethane is one of the most widely used polymer materials in the world. With the increasing demand of polyurethane, its mechanical behaviors are particularly of interest. In particular, the response of the material under a quasi-static loading being subject to an impact load. To delineate the effect of rate change on the mechanical response of polyurethane, a tensile experiment was designed where the specimen is initially subjected to quasi-static tensile loading and then to high-rate cyclic tension within the same experiment. Constant strain-rate experiments at both quasi-static and high strain rates are also conducted. The analysis of the results leads …

Modeling Of Frame Structures Undergoing Large Deformations And Large Rotations, Hui Liu

Open Access Dissertations

Numerical simulation of large-scale problems in structural dynamics, such as structures subject to extreme loads, can provide useful insights into structural behavior while minimizing the need for expensive experimental testing for the same. These types of problems are highly non-linear and usually involve material damage, large deformations and sometimes even collapse of structures. Conventionally, frame structures have been modeled using beam-frame finite elements in almost all structural analysis software currently being used by researchers and the industry. However, there are certain limitations associated with this modeling approach. This research focuses on two issues, in particular, of modeling frame structures undergoing …

High-Throughput Mechanical Characterization Methods For Composite Electrodes And In-Situ Analysis Of Li-Ion Batteries, Luize Scalco De Vasconcelos

Open Access Theses

Electrodes in commercial rechargeable batteries are microscopically heterogeneous materials. The constituents often have large variation in their mechanical properties, making the characterization process a challenging task. In addition, the mechanical properties and mechanical behaviors of electrodes are closely coupled with the electrochemical processes of lithium insertion and extraction. There is an urgent need to develop an experimental platform to characterize the chemomechanical response of electrodes under the in-situ conditions of charge and discharge.

In the first part of this thesis, instrumented grid indentation is employed to determine the elastic modulus and hardness of the constituent phases of a composite cathode. …

Multi-Axial Failure Of High-Performance Fiber During Transverse Impact, Matthew C. Hudspeth

Open Access Dissertations

The effect of projectile nose geometry on ensuing wave development in high-performance yarns is explored during single yarn transverse impact. Special attention has been placed on visualizing the immediate region around the projectile-yarn contact site for 0.30-cal round, 0.30-cal fragment simulation projectiles (FSP), and razor blades using high-speed imaging. Kevlar® KM2, Dyneema®SK76 and AuTx have been impacted at velocities ranging from ∼100 m/s to ∼1200 m/s depending on projectile nose shape, with an emphasis set on determining the critical velocity wherein below said velocity significant development of wave propagation occurs and above said velocity the yarn fails immediately upon impact. …

Mixed Mesh/Nodal Magnetic Equivalent Circuit Modeling Of A Six-Phase Claw-Pole Automotive Alternator, Daniel C. Horvath

Open Access Theses

Magnetic equivalent circuits (MECs) have been employed by many researchers to model the relationship between magnetic flux and current in electromagnetic systems such as electric machines, transformers and inductors [1] ,[2]. Magnetic circuits are analogous to electric circuits where voltage, current, resistance and conductance are the respective counterparts of magneto-motive force (MMF), magnetic flux, reluctance and permeance. The solution of MECs can be accomplished with the plethora of techniques developed for electrical circuit analysis. Specifically, mesh analysis, based on Kirchoff’s Voltage Law (KVL), and nodal analysis, based on Kirchoffs Current Law (KCL), are two very common solution techniques. Once an …

Simulation, Control And Testing Of Advanced Hydraulic Hybrid Transmissions, Italo M. Ramos, Monika Ivantysynova, Michael Sprengel

The Summer Undergraduate Research Fellowship (SURF) Symposium

Hydraulic hybrids transmissions have the potentially to substantially improve the fuel efficiency of on road vehicles. In fact recent studies have demonstrated that this technology can improve fuel economy by upwards of 30% over competing electric hybrids. To further improve the fuel economy and performance of this technology a novel blended hydraulic hybrid transmission has been constructed at the Maha Fluid Power Research Center. While this novel hybrid architecture created by the Maha lab has many benefits over conventional systems, there are a number of control challenges present due to several discrete modes of operation. And though improving fuel economy …

Development Of A Shape Memory Polymer Soft Microgripper, Marshall Tatro, David J. Cappelleri, Wuming Jing

The Summer Undergraduate Research Fellowship (SURF) Symposium

The ability to control microrobots by means of magnetic fields has become of increasing interest to researchers. These robots’ ability to reach places tethered microrobots otherwise could not leads to many possible applications in the body, such as delivering drugs to targeted locations and performing biopsies. This study shows the use of shape memory polymer (SMP) to wirelessly actuate a microgripper to be used by a controllable microrobot to achieve these functions. Many smart materials were analyzed in order to find the material that most effectively would accomplish wirelessly gripping, manipulating, and releasing a microobject. Multiple microgripper designs were designed, …

Efficient Exploration Of Quantified Uncertainty In Granular Crystals, Juan C. Lopez Ramirez, Marcial Gonzalez, Ilias Bilionis, Rohit K. Tripathy

The Summer Undergraduate Research Fellowship (SURF) Symposium

Granular crystals present unique nonlinear properties that support standing waves. These depend on precompression and impurities. Thus, they can be used for different applications such as impact and shock dissipation. There are different models which rely on reasonable approximations and assumptions. While experimental results show good agreement with theory, there are experimental errors that are not easily explained and are usually attributed to the approximations made and phenomena that are not accounted for. This might be the result of not quantifying the uncertainty, since variables like the grain size, position, mass and Young modulus, of each particle, are uncertain. Building …

Fully Electronic Method Of Measuring Post-Release Gap And Gradient/Residual Stress Of A Mems Cantilever, Andrew Stephen Kovacs

Open Access Dissertations

Smartphones and other wireless devices have become ubiquitous over the past decade, and the RF front-end inside of them has become more complex and disproportionately consumes more power compared to other components. Micro-electromechanical systems (MEMS) have a huge potential to reduce these problems while simultaneously offering superior performance compared to current leading-edge technology. However, MEMS technology has difficulty transitioning from the lab to large-scale manufacturing due to the unpredictability of device lifetime and manufacturability issues. This can be mitigated by investigating how critical material or physical parameters (gap, stress, Young's modulus, material thickness, etc.) vary from manufacturing uncertainties and how …

Asymptotic Modelling Of A Thermopiezoelastic Anisotropic Smart Plate, Yufei Long

Open Access Theses

Motivated by the requirement of modelling for space flexible reflectors as well as other applications of plate structures in engineering, a general anisotropic laminated thin plate model and a monoclinic Reissner-Mindlin plate model with thermal deformation, two-way coupled piezoelectric effect and pyroelectric effect is constructed using the variational asymptotic method, without any ad hoc assumptions. Total potential energy contains strain energy, electric potential energy and energy caused by temperature change. Three-dimensional strain field is built based on the concept of warping function and decomposition of the rotation tensor. The feature of small thickness and large in-plane dimension of plate structure …

A Contribution Toward Better Understanding Of Overbanking Tendency In Fixed-Wing Aircraft, Nihad E. Daidzic

Journal of Aviation Technology and Engineering

The phenomenon of overbanking tendency for a rigid-body, fixed-wing aircraft is investigated. Overbanking tendency is defined as a spontaneous, unbalanced rolling moment that keeps increasing an airplane’s bank angle in steep turns and must be arrested by opposite aileron action. As stated by the Federal Aviation Administration, the overbanking tendency may lead to a loss of control, especially in instrument meteorological conditions. It was found in this study that the speed differential over wing halves in horizontal turns indeed creates a rolling moment that achieves maximum values for bank angles between 45 and 55 degrees. However, this induced rolling moment …

Structure-Thermal Coupling In Viscoelastic Material In Rubber Bushing Of Vehicle System, Zhengui Zhang

Open Access Dissertations

The objective of this research is to utilize the frequency-dependent viscoelastic material model and characterize the dynamic response of rubber bushing under external excitation. Furthermore, with appropriate modeling, two heat generation mechanisms of rubber bushing are explored and their thermal fields are investigated. Due to the nonlinear force-deflection relationship of the viscoelastic material, finding satisfactory mechanical properties of rubber components still poses a great challenge. However, industry nowadays is in urgent demand for precise finite element analysis (FEA) modeling of rubber components. For example, a proper constitutive relationship of rubber components is critical to providing a reliable and trustable simulation …

Simulations Of Diffusion Driven Phase Evolution In Heterogenous Solids, Subramanya Gautam Sadasiva

Open Access Dissertations

With reduction in size, ever greater operational demands are placed on electronics components at all levels of the device, starting from the transistor level to the level of the package and the solder interconnects. Concurrently, there has been a move to more complicated materials systems in order to meet health and environmental guidelines. These trends of reducing size, increasing loads have increased the necessity to understand the mechanisms of the failure. ^ As the length scales are reduced, it becomes increasingly important to consider interfacial and micro-structural effects that can be safely ignored at larger length scales owing to the …

Microstructure Development Of Granular System During Compaction, Chen Shang, Marcial Gonzalez

The Summer Undergraduate Research Fellowship (SURF) Symposium

Granular materials is the second most manipulated material in the industry today. They are easy to transport and more and more newly developed materials cannot stand the process of traditional casting, like energetic materials and bio-materials, but will survive the powder compaction process. Having a better understanding of the microstructure development of granular systems during compaction process, especially for particles that will heavily deform under loading, will give an insight of how to better process the powders to produce materials with overall better performance comparing to bulk materials. The main theory and mechanism applied are Hertz law and nonlocal contact …

Transverse Compression Of High-Performance Ballistic Fibers, Zherui Guo

Open Access Theses

High performance ballistic fibers have been in use for decades, specifically in protective applications against ballistic impact such as bulletproof vest layers and aircraft turbine engine fragmentation barriers. These high performance fibers have extremely high strength-to-weight ratios and high moduli of elasticity in the axial direction, making them extremely suitable for high impact situations. In particular, para-phenyleneterephthalamide (PPTA for short) fibers such as Kevlar^® and ultra-high-molecular-weight polyethylene fibers such as Dyneema^® are amongst the more popular high performance fibers in today's world. While the longitudinal mechanical response of these fibers have been extensively researched, their transverse mechanical response …