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Full-Text Articles in Mechanical Engineering

Intuity Sleeve Redesign, Maxwell Arnold, Brittany Kinkade, Dominic Nicoletti Jun 2013

Intuity Sleeve Redesign, Maxwell Arnold, Brittany Kinkade, Dominic Nicoletti

Mechanical Engineering

No abstract provided.


Adaptive Floor Hockey Device, Chris Gaul, Ricardo Gaytan, Matt Spaulding, Shannon Brant Jun 2013

Adaptive Floor Hockey Device, Chris Gaul, Ricardo Gaytan, Matt Spaulding, Shannon Brant

Mechanical Engineering

Sean is a young boy living with ataxic cerebral palsy. Ataxic cerebral

palsy affects Sean’s balance and coordination, so he uses a walker to

increase his mobility. Sean would like to play Special Olympics Floor

Hockey but his walker prevents him from participating. The goal of this

Senior project was to develop a device to be attached to his previous

walker to allow Sean to play floor hockey in the least restrictive

environment possible. The Adaptive Floor Hockey Device is the product

we designed to satisfy this need.


Design And Development Of A Stair Ascension Assistive Device For Transfemoral Amputees, Casey Michael Barbarino Jun 2013

Design And Development Of A Stair Ascension Assistive Device For Transfemoral Amputees, Casey Michael Barbarino

Master's Theses

Transfemoral amputees around the world experience increased difficulty in climbing stairs due to lack of muscle, balance, and other factors. The loss of a lower limb greatly diminishes the amount of natural force generation provided that is necessary to propel oneself up stairs. This study investigated possible solutions to the problem of stair ascension for transfemoral amputees by the means of designing and developing an externally attachable device to a prosthesis. The number of amputations from military service has greatly increased since 2008, which shows there is a clear need for assistive devices (Wenke, Krueger, & Ficke, 2012). With the …


Design And Testing Of A Low Cost Prosthetic Foot, Shalan Ertis, John Kearns, Seija Maniskas Jun 2012

Design And Testing Of A Low Cost Prosthetic Foot, Shalan Ertis, John Kearns, Seija Maniskas

Mechanical Engineering

No abstract provided.


Hydraulically Driven Mechanical Representation Of A Biological System, Andrea Argouarch, Michael Mceachern, Brandon Parham Jun 2012

Hydraulically Driven Mechanical Representation Of A Biological System, Andrea Argouarch, Michael Mceachern, Brandon Parham

Biomedical Engineering

No abstract provided.


Polygrasp: Reach; Myoelectric Prosthetic Hand Iteration, Devon Patrick Augustus, Mighells Blaed Deuel, Ian Noel Fraser, Nicholas Philip Moesser Jun 2012

Polygrasp: Reach; Myoelectric Prosthetic Hand Iteration, Devon Patrick Augustus, Mighells Blaed Deuel, Ian Noel Fraser, Nicholas Philip Moesser

Mechanical Engineering

Amputations are a common occurrence in soldiers returning home who have suffered the effects of IED and munitions explosions. For upper limb amputees, trans-radial amputations are the most common. Traditional hook devices do not offer an adequate level of normalcy for users, prompting the use of myoelectric devices. While current myoelectric devices do offer a more natural experience, they come with a host of other problems that makes their adoption by service personnel not desirable or not permitted by the VA. PolyGrasp Reach seeks to reduce weight and cost and improve performance. This addresses several of the issues with devices …


Viscoelastic Anisotropic Finite Element Mixture Model Of Articular Cartilage Using Viscoelastic Collagen Fibers And Validation With Stress Relaxation Data, Matthew Alexander Griebel Jun 2012

Viscoelastic Anisotropic Finite Element Mixture Model Of Articular Cartilage Using Viscoelastic Collagen Fibers And Validation With Stress Relaxation Data, Matthew Alexander Griebel

Master's Theses

Experimental results show that collagen fibers exhibit stress relaxation under tension and a highly anisotropic distribution. To further develop the earlier model of Stender [1], the collagen constituent was updated to reflect its intrinsic viscoelasticity and anisotropic distribution, and integrated with an existing mixture model with glycosaminoglycans and ground substance matrix. A two-term Prony series expansion of the quasi-linear viscoelastic model was chosen to model the viscoelastic properties of the collagen fibers. Material parameters were determined by using the simplex method to minimize the sum of squared errors between model results and experimental stress relaxation data of tissue in tension. …


Prediction Of Articular Cartilage Remodeling During Dynamic Compression With A Finite Element Model, Kevin Akira Yamauchi Jun 2012

Prediction Of Articular Cartilage Remodeling During Dynamic Compression With A Finite Element Model, Kevin Akira Yamauchi

Master's Theses

First, an in vitro growth experiment was performed to test the hypothesis that applying dynamic unconfined compression during culture produces het- erogeneous remodeling in newborn bovine articular cartilage explants. Het- erogeneous measures of cartilage microstructure were obtained by biochemical assays and quantified polarized light microscopy. Significant differences were measured between the GAG content in the inner and outer portions of the sam- ples stimulated with dynamic unconfined compression. The COL fiber network was found to be more highly aligned in the inner portion of the sample than in the peripheral region.

Next, a poroelastic finite element model with a remodeling …


Golf Prosthesis Final Design Report, Joseph Barcus, Lauren Wilson, Ryan Satcher Dec 2011

Golf Prosthesis Final Design Report, Joseph Barcus, Lauren Wilson, Ryan Satcher

Mechanical Engineering

A prosthetic attachment designed to allow an upper extremity bilateral amputee to golf.


Challenger J Hockey Prosthesis Final Design Report, Ryan Bakker, Spencer Noe, Christopher Perkins Dec 2011

Challenger J Hockey Prosthesis Final Design Report, Ryan Bakker, Spencer Noe, Christopher Perkins

Mechanical Engineering

The content of this report is withheld as confidential. QL+ is the owner of the intellectual property created throughout the duration of this project. Dr. Tom Mase (mechanical engineering) maintains a full copy of the report and intends to disseminate it upon completion of the necessary intellectual property protection measures.


Access|Closure Balloon Catheter Redesign Project, Keenan Bamburg, Yvette Castillo, Elizabeth Eskildsen Dec 2011

Access|Closure Balloon Catheter Redesign Project, Keenan Bamburg, Yvette Castillo, Elizabeth Eskildsen

Mechanical Engineering

No abstract provided.


Rock-N-Bowler Ii, Josh Grip, Travis Rodrigues, Richard Rozporka Jun 2011

Rock-N-Bowler Ii, Josh Grip, Travis Rodrigues, Richard Rozporka

Mechanical Engineering

The report of the creation of an adaptive bowling device designed for people in powered wheelchairs. The basic design is a ramp that attaches to the wheelchair and has the ability to add spin to the ball to allow the user to hook the ball.


Poroelastic Finite Element Analysis Of A Heterogeneous Articular Cartilage Explant Under Dynamic Compression In Abaqus, Kelsey Kiyo Kam Jun 2011

Poroelastic Finite Element Analysis Of A Heterogeneous Articular Cartilage Explant Under Dynamic Compression In Abaqus, Kelsey Kiyo Kam

Master's Theses

A poroelastic finite element model of a heterogeneous articular cartilage disc was

created to examine the tissue response to low amplitude (± 2% strain), low

frequency (0.1 Hz) dynamic unconfined compression (UCC). A strong correlation

has been made between the relative fluid velocity and stimulation of

glycosaminoglycan synthesis. A contour plot of the model shows the relative fluid

velocity during compression exceeds a trigger value of 0.25 μm/s at the radial

periphery. Dynamic UCC biochemical results have also reported a higher

glycosaminoglycan content in this region versus that of day 0 specimens. Fluid

velocity was also found not to be …


Predicting Articular Cartilage Constituent Material Properties Following In Vitro Growth Using A Proteoglycan-Collagen Mixture Model, Michael Stender Mar 2011

Predicting Articular Cartilage Constituent Material Properties Following In Vitro Growth Using A Proteoglycan-Collagen Mixture Model, Michael Stender

Master's Theses

A polyconvex continuum-level proteoglycan Cauchy stress function was developed based on the continuum electromechanical Poisson-Boltzmann unit cell model for proteoglycan interactions. The resulting proteoglycan model was combined with a novel collagen fibril model and a ground substance matrix material to create a polyconvex constitutive finite element model of articular cartilage. The true collagen fibril modulus , and the ground substance matrix shear modulus , were varied to obtain the best fit to experimental tension, confined compression, and unconfined compression data for native explants and explants cultured in insulin-like growth factor-1 (IGF-1) and transforming growth factor-β1 (TGF-β1). Results indicate …


Low-Cost Prosthetic Leg For The Vida Nueva Prosthesis Clinic, Sarah M. Baker, Justin G. Lekos, Jen Van Donk, Kevin Yamauchi Jan 2011

Low-Cost Prosthetic Leg For The Vida Nueva Prosthesis Clinic, Sarah M. Baker, Justin G. Lekos, Jen Van Donk, Kevin Yamauchi

Mechanical Engineering

The Piernas de Vida team partnered with the Vida Nueva Clinic of Prostheses and Orthoses in Choluteca, Honduras to design, plan, and implement a prosthetic foot that could be manufactured entirely by the technicians at the clinic in order to reduce their costs and ultimately allow them to serve more patients each year. Currently, the clinic uses a prefabricated prosthetic lower limb provided by the International Committee of the Red Cross (ICRC) which can be adapted to both transDfemoral and transDtibial patients. The team has successfully developed a foot, currently called the Layer Foot, which can be used by the …


Edwards Lifesciences: Heart Valve Tension Validation, Lucas Fochler, Alex Mark, Shilpan Shah Jun 2010

Edwards Lifesciences: Heart Valve Tension Validation, Lucas Fochler, Alex Mark, Shilpan Shah

Mechanical Engineering

No abstract provided.


Strider, Eric Johnson, Alex Trask, Ricardo Garcia Jun 2010

Strider, Eric Johnson, Alex Trask, Ricardo Garcia

Mechanical Engineering

No abstract provided.


Medtronic Universal Crimping Machine, Justin Ginochio, Andrew Hanson, Zachary (Zach) Dieterle Jun 2010

Medtronic Universal Crimping Machine, Justin Ginochio, Andrew Hanson, Zachary (Zach) Dieterle

Mechanical Engineering

This project is geared towards the redesign and implementation of a crimping tool for use in the manufacturing of catheters produced by Medtronic Inc. Catheters require two steering cables to maneuver the end of the catheter through the body. The steering cables have a sleeve that is crimped onto their end in order to hold the cable in place inside the catheter steering handle. The current crimping tool, designed by Astro Tool Corp, has a few problems associated with its design. Additionally we are trying to get rid of a step in the manufacturing process that involves the adhesive, cyanoacrylate, …


An Investigation Of Humeral Stress Fractures In Racing Thoroughbreds Using A 3d Finite Element Model In Conjunction With A Bone Remodeling Algorithm, Ryan James Moore Feb 2010

An Investigation Of Humeral Stress Fractures In Racing Thoroughbreds Using A 3d Finite Element Model In Conjunction With A Bone Remodeling Algorithm, Ryan James Moore

Master's Theses

The humerus of a racing horse Thoroughbred is highly susceptible to stress fractures at a characteristic location as a result of cyclic loading. The propensity of a Thoroughbred to exhibit humeral fracture has made equines useful models in the epidemiology of stress fractures. In this study, a racing Thoroughbred humerus was simulated during training using a 3D finite element model in conjunction with a bone remodeling algorithm. Nine muscle forces and two contact forces were applied to the 3-dimensional finite element model, which contains four separate load cases representing fore-stance, mid-stance, aft-stance, and standing. Four different training programs were incorporated …


Mechanical Simulation Of Articular Cartilage Based On Experimental Results, Kevin Matthew Stewart Jun 2009

Mechanical Simulation Of Articular Cartilage Based On Experimental Results, Kevin Matthew Stewart

Master's Theses

Recently, a constituent based cartilage growth finite element model (CGFEM) was developed in order to predict articular cartilage (AC) biomechanical properties before and after growth. Previous research has noted limitations in the CGFEM such as model convergence with growth periods greater than 12 days. The main aims of this work were to address these limitations through (1) implementation of an exact material Jacobian matrix definition using the Jaumann-Kirchhoff (J-K) method and (2) quantification of elastic material parameters based upon research findings of the Cal Poly Cartilage Biomechanics Group (CPGBG). The J-K method was successfully implemented into the CGFEM and exceeded …


Simulating The Growth Of Articular Cartilage Explants In A Permeation Bioreactor To Aid In Experimental Protocol Design, Timothy P. Ficklin, Andrew Davol, Stephen M. Klisch Apr 2009

Simulating The Growth Of Articular Cartilage Explants In A Permeation Bioreactor To Aid In Experimental Protocol Design, Timothy P. Ficklin, Andrew Davol, Stephen M. Klisch

Mechanical Engineering

Recently a cartilage growth finite element model (CGFEM) was developed to solve nonhomogeneous and time-dependent growth boundary-value problems (Davol et al., 2008, “A Nonlinear Finite Element Model of Cartilage Growth,” Biomech. Model. Mechanobiol., 7, pp. 295–307). The CGFEM allows distinct stress constitutive equations and growth laws for the major components of the solid matrix, collagens and proteoglycans. The objective of the current work was to simulate in vitro growth of articular cartilage explants in a steady-state permeation bioreactor in order to obtain results that aid experimental design. The steady-state permeation protocol induces different types of mechanical stimuli. When the specimen …


Articular Cartilage Tensile Integrity: Modulation By Matrix Depletion Is Maturation-Dependent, Anna Asanbaeva, Johnny Tam, Barbara L. Schumacher, Stephen M. Klisch, Koichi Masuda, Robert L. Sah Jun 2008

Articular Cartilage Tensile Integrity: Modulation By Matrix Depletion Is Maturation-Dependent, Anna Asanbaeva, Johnny Tam, Barbara L. Schumacher, Stephen M. Klisch, Koichi Masuda, Robert L. Sah

Mechanical Engineering

Articular cartilage function depends on the molecular composition and structure of its extracellular matrix (ECM). The collagen network (CN) provides cartilage with tensile integrity, but must also remodel during growth. Such remodeling may depend on matrix molecules interacting with the CN to modulate the tensile behavior of cartilage. The objective of this study was to determine the effects of increasingly selective matrix depletion on tensile properties of immature and mature articular cartilage, and thereby establish a framework for identifying molecules involved in CN remodeling. Depletion of immature cartilage with guanidine, chondroitinase ABC, chondroitinase AC, and Streptomyces hyaluronidase markedly increased tensile …


A Cartilage Growth Mixture Model With Collagen Remodeling: Validation Protocols, Stephen M. Klisch, Anna Asanbaeva, Sevan R. Oungoulian, Koichi Masuda, Eugene J.-Ma. Thonar, Andrew Davol, Robert L. Sah Jun 2008

A Cartilage Growth Mixture Model With Collagen Remodeling: Validation Protocols, Stephen M. Klisch, Anna Asanbaeva, Sevan R. Oungoulian, Koichi Masuda, Eugene J.-Ma. Thonar, Andrew Davol, Robert L. Sah

Mechanical Engineering

A cartilage growth mixture (CGM) model is proposed to address limitations of a model used in a previous study. New stress constitutive equations for the solid matrix are derived and collagen (COL) remodeling is incorporated into the CGM model by allowing the intrinsic COL material constants to evolve during growth. An analytical validation protocol based on experimental data from a recent in vitro growth study is developed. Available data included measurements of tissue volume, biochemical composition, and tensile modulus for bovine calf articular cartilage (AC) explants harvested at three depths and incubated for 13 days in 20% fetal borine serum …


A Growth Mixture Theory For Cartilage With Application To Growth-Related Experiments On Cartilage Explants, Stephen M. Klisch, Silvia S. Chen, Robert L. Sah, Anne Hoger Apr 2003

A Growth Mixture Theory For Cartilage With Application To Growth-Related Experiments On Cartilage Explants, Stephen M. Klisch, Silvia S. Chen, Robert L. Sah, Anne Hoger

Mechanical Engineering

In this paper, we present a growth mixture model for cartilage. The main features of this model are illustrated in a simple equilibrium boundary-value problem that is chosen to illustrate how a mechanical theory of cartilage growth may be applied to growth-related experiments on cartilage explants. The cartilage growth mixture model describes the independent growth of the proteoglycan and collagen constituents due to volumetric mass deposition, which leads to the remodeling of the composition and the mechanical properties of the solid matrix. The model developed here also describes how the material constants of the collagen constituent depend on a scalar …


A Growth Mixture Theory For Cartilage, Stephen M. Klisch, Robert L. Sah, Anne Hoger Nov 2000

A Growth Mixture Theory For Cartilage, Stephen M. Klisch, Robert L. Sah, Anne Hoger

Mechanical Engineering

In this paper we present a model of growth for cartilaginous tissues in which there exists a saturated solid matrix composed of multiple constituents that may grow and remodel independently of each other. Klisch and Hoger recently developed a general theory of volumetric growth for a mixture of ν-1 growing elastic materials and an inviscid fluid, which included a treatment of two special types of internal constraints that are relevant to cartilage. Here, that theory is specialized to construct a cartilage growth model. This theory allows the constituents of the solid matrix to grow independently of each other, and can …


A Special Theory Of Biphasic Mixtures And Experimental Results For Human Annulus Fibrosus Tested In Confined Compression, Stephen M. Klisch, Jeffrey C. Lotz Apr 2000

A Special Theory Of Biphasic Mixtures And Experimental Results For Human Annulus Fibrosus Tested In Confined Compression, Stephen M. Klisch, Jeffrey C. Lotz

Mechanical Engineering

A finite deformation mixture theory is used to quantify the mechanical properties of the annulus fibrosus using experimental data obtained from a confined compression protocol. Certain constitutive assumptions are introduced to derive a special mixture of an elastic solid and an inviscid fluid, and the constraint of intrinsic incompressibility is introduced in a manner that is consistent with results obtained for the special theory. Thirty-two annulus fibrosus specimens oriented in axial (n = 16) and radial (n = 16) directions were obtained from the middle-lateral portion of intact intervertebral discs from human lumbar spines and tested in a stress-relaxation protocol. …