Open Access. Powered by Scholars. Published by Universities.®

Mechanical Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 5 of 5

Full-Text Articles in Mechanical Engineering

Piezoelectric Bistable Buckled Beam Energy Harvester., Brian Edward Allgeier Aug 2017

Piezoelectric Bistable Buckled Beam Energy Harvester., Brian Edward Allgeier

Electronic Theses and Dissertations

A novel energy harvesting device design is presented to be created via microfabrication techniques. Such devices have countless applications for powering low-current electrical devices, especially wireless sensors or transmitters. This micro-electromechanical system (MEMS) design utilizes the piezoelectric response of a bistable buckled beam to gather electrical energy via ambient vibrations. While many traditional piezoelectric energy harvesters (PEH) consist of simple cantilever beam geometries, this nonlinear design utilizes inertial effects of torsional lever arms to actuate a central buckled beam to snap between its two stable states; such an abrupt strain on the piezoelectric beam potentially produces a significantly increased electrical …


Development And Evaluation Of A Biocompatible Electroactive Sensor For Continuous Blood Pressure Measurement., Scott D. Cambron May 2017

Development And Evaluation Of A Biocompatible Electroactive Sensor For Continuous Blood Pressure Measurement., Scott D. Cambron

Electronic Theses and Dissertations

Piezo-active composites have been implemented for sensing and transduction for decades. The 0-3 ceramic/polymer composite is one of the most common composite types used for sensing applications, owing to their tailorable properties of the two-phase composition, consisting of a three-dimensionally connected polymer/rubber matrix (inactive phase) with a dispersion of isolated piezo-ceramic particles (active phase). This thesis describes a method to develop novel biocompatible perivascular band comprised of a two-phase piezo-active composite to be fabricated using simple manufacturing processes. Biomaterials such as tissue scaffolds comprised of silk fibroin (SF) and chitosan (CS), and biocompatible soft rubbers will be implemented as the …


Some Experimental Investigation On Effect Of Light And Vibration On Nano Coated Piezo For Energy Harvesting, Abhay Sharma Jan 2015

Some Experimental Investigation On Effect Of Light And Vibration On Nano Coated Piezo For Energy Harvesting, Abhay Sharma

Electronic Theses and Dissertations

PZT is a promising piezoelectric ceramic material which has a wide range of applications in a variety of fields such as acoustic sensors and transducers, electrical switches, medical instrumentation, artificial sensitive skin in robotics, automotive detection on roads, nondestructive testing , structural health monitoring and as a biocompatible material. In this research a cantilever based multi energy harvester was developed to maximize the power output of PZT sensor. Nano mixtures containing graphene, ferrofluid nanoparticle (FNP) and ZnO nano particles were used to enhance the piezoelectric and photovoltaic output of the sensor. The samples were tested under different energy conditions to …


Structural Analysis And Active Vibration Control Of Tetraform Space Frame For Use In Micro-Scale Machining, Kevin Knipe Jan 2009

Structural Analysis And Active Vibration Control Of Tetraform Space Frame For Use In Micro-Scale Machining, Kevin Knipe

Electronic Theses and Dissertations

This research thesis aims to achieve the structural analysis and active vibration damping of the Tetraform machining structure. The Tetraform is a space frame made up of four equilateral triangles with spherical masses at the four vertices. This frame was originally developed for grinding of optical lenses and is now being adapted for use in micro-precision milling. The Tetraform is beneficial to the milling process due to its exceptionally high dynamic stiffness characteristics, which increases the machining stability and allows for higher material removal rates and accuracy. However, there are still some modes of vibration that are critical to the …


Finite Element Simulation Of Repair Of Delaminated Composite Structures Using Piezoelectric Layers, Kunal Navale Jan 2005

Finite Element Simulation Of Repair Of Delaminated Composite Structures Using Piezoelectric Layers, Kunal Navale

Electronic Theses and Dissertations

Damage in composite material fabricated aerospace, aeronautical, mechanical, civil and offshore structures often results from factors such as fatigue, corrosion and accidents. Such damage when left unattended can grow at an alarming rate due to the singularity of the stress and strain in the vicinity of the damage. It can lead to increase in the vibration level, reduction in the load carrying capacity, deterioration in the normal performance of the component and even catastrophic failure. In most conditions, the service life of damaged components is extended with repair instead of immediate replacement. Effective repair of structural damage is therefore an …