Engineering Commons^™

Design Of Shape-Morphing Structures Consisting Of Bistable Compliant Mechanisms, Rami Alfattani

USF Tampa Graduate Theses and Dissertations

This dissertation presents a design concept for shape-morphing structures that have two stable configurations. The design concept defines the methodology of transforming a planar structural shape into spatial structural shape using bistable compliant mechanisms. Bistable complaint mechanisms are used to achieve structural stable configurations. The dissertation incorporating geometrical relationships for the mechanisms that form the primary structure described in step-by-step process. This dissertation implements the design layouts for designer to creating shape-morphing structures including origami. The novel contribution of the work is classified in three models. The first model presents a methodology to induce bistability behavior into an origami reverse …

Developing Motion Platform Dynamics For Studying Biomechanical Responses During Exercise For Human Spaceflight Applications, Kaitlin Lostroscio

USF Tampa Graduate Theses and Dissertations

In future human spaceflight missions, with prolonged exposure to microgravity, resistive and aerobic exercises will be countermeasures for bone loss, muscle loss, and decreased aerobic capacity. Two of the exercises of interest are squats and rowing. The cyclic forces produced during these exercises are at relatively low frequencies which are likely to excite structural resonances of space vehicles. Vibration Isolation Systems (VIS) are being designed to be paired with future exploration exercise devices in order to prevent these cyclic exercise forces from impacting the space vehicle. The VIS may be configured such that a platform supports the human and exercise …

The Development Of A Platform Interface With The Use Of Virtual Reality To Enhance Upper-Extremity Prosthetic Training And Rehabilitation, Ashley D. Knight

USF Tampa Graduate Theses and Dissertations

This dissertation focuses on the investigation and development of an effective prosthetic training and rehabilitation platform with the use of virtual reality to facilitate an effective process to return amputees to the highest level of independence and functioning possible.

It has been reported that approximately 10 million people live with a limb loss worldwide, with around 30% being an upper-extremity amputee. The sudden loss of a hand or arm causes the loss of fine, coordinated movements, reduced joint range of motion (ROM), proprioceptive feedback and aesthetic appearance, all which can be improved with the use of a prosthesis and proper …

A Planar Pseudo-Rigid-Body Model For Cantilevers Experiencing Combined Endpoint Forces And Uniformly Distributed Loads Acting In Parallel, Philip James Logan

USF Tampa Graduate Theses and Dissertations

This dissertation describes the development and effectiveness of a mathematical model used to predict the behavior of cantilever beams whose loading conditions include parallel combinations of evenly distributed loads and endpoint forces. The large deflection of cantilever beams has been widely studied. A number of models and mathematical techniques have been utilized in predicting the endpoint path coordinates and load-deflection relationships of such beams. The Pseudo-Rigid-Body Model (PRBM) is one such method which replaces the elastic beam with rigid links of a parameterized pivot location and torsional spring stiffness. In this paper, the PRBM method is extended to include cases …

Pseudo-Rigid-Body Models For Approximating Spatial Compliant Mechanisms Of Rectangular Cross Section, Issa Ailenid Ramirez

USF Tampa Graduate Theses and Dissertations

The objective of the dissertation is to develop and describe kinematic models (Pseudo-Rigid-Body Models) for approximating large-deflection of spatial (3D) cantilever beams that undergo multiple bending motions thru end-moment loading. Those models enable efficient design of compliant mechanisms, because they simply and accurately represent the bending and stiffness of compliant beams.

To accomplish this goal, the approach can be divided into three stages: development of the governing equations of a flexible cantilever beam, development of a PRBM for axisymmetric cantilever beams and the development of spatial PRBMs for rectangular cross-section beam with multiple end moments.

The governing equations of a …

Using Embedded Systems To Determine The Configuration Of A Static Wheelchair Mounted Robotic Arm, Daniel Ashley

USF Tampa Graduate Theses and Dissertations

The calibration of a 9 degree of freedom (DOF) robotic manipulator using multiple three axis accelerometers and an embedded system will be accomplished in this work. The 9-DOF robotic system used in this study is a 7-DOF robotic arm attached to a 2-DOF power wheelchair. Combined they create a Wheelchair Mounted Robotic Arm (WMRA). The problem that will be solved by this thesis is the calibration of the robotic system during start up. The 7 DOF robotic arm is comprised of rotational joints only. These joints have dual channel encoders to determine the joint position, among other useful data. The …

A 3-D Pseudo-Rigid-Body Model For Rectangular Cantilever Beams With An Arbitrary Force End-Load, Jairo Renato Chimento

USF Tampa Graduate Theses and Dissertations

This dissertation introduces a novel three-dimensional pseudo-rigid-body model (3-D PRBM) for straight cantilever beams with rectangular cross sections. The model is capable of capturing the behavior of the neutral axis of a beam loaded with an arbitrary force end-load. Numerical integration of a system of differential equations yields approximate displacement and orientation of the beam's neutral axis at the free end, and curvatures of the neutral axis at the fixed end. This data was used to develop the 3-D PRBM which consists of two torsional springs connecting two rigid links for a total of 2 degrees of freedom (DOF). The …

Shield Design For Maximum Deformation In Shape-Shifting Surfaces, Daniel Eduardo Perez

USF Tampa Graduate Theses and Dissertations

This research presents the initial studies and results on shield design for Shape-Shifting Surfaces (SSSs) seeking maximum compression and maximum expansion of a unit-cell. Shape-Shifting Surfaces (SSSs) are multilayered surfaces that are able to change shape while maintaining their integrity as physical barriers. SSSs are composed of polygonal unit-cells, which can change side lengths and corner angles. These changes are made possible by each side and corner consisting of at least two different shields, or layers of material. As the layers undergo relative motion, the unit-cell changes shape. In order for the SSS to retain its effectiveness as a barrier, …

Multistable Shape-Shifting Surfaces (Mssss), Paul Joseph Montalbano

USF Tampa Graduate Theses and Dissertations

This paper presents designs for Multistable Shape-Shifting Surfaces (MSSS) by introducing bistability into the Shape-Shifting Surface (SSS). SSSs are defined as surfaces that retain their effectiveness as a physical barrier while undergoing changes in shape. The addition of bistability to the SSS gives the surface multiple distinct positions in which it remains when shifted to, i.e. by designing bistability into a single SSS link, the SSS unit cell can change into multiple shapes, and stabilize within the resulting shape, while maintaining integrity against various forms of external assaults normal to its surface. Planar stable configurations of the unit cell include, …

A Mechanized Horseback Riding Simulator As An Aid To Physical Therapy, Jennifer Lott

USF Tampa Graduate Theses and Dissertations

Equine-assisted therapy is a nontraditional form of physical therapy that involves riding horses as a form of rehabilitation. Limited access to these riding programs justifies a need to develop a horseback riding simulator capable of simulating the gaits, bend, and collection of the horse. Research involving the development of horseback riding simulators is limited, but the available research does show promising results in the ability to aid in physical therapy.

A two-dimensional model and simulation was developed using MATLAB. Using the results from the simulation, a horseback riding simulator was designed, fabricated and tested. The physical simulator was capable of …