Department of Mechanical Engineering
Mississippi State University
Biologically Inspired Piezoelectric Morphing: By adding a layer of angled piezoelectric segments to a Pb(Zr,Ti)O3 (also referred to as PZT) bimorph actuator, a bend-twist coupling may be introduced to the flexural response of the layered PZT, thereby creating a biaxial actuator capable of driving wing oscillation in flapping wing MAVs. The present study presents numerical investigation of the response of functionally–modified bimorph designs intended for active bend-twist actuation of cm-scale flapping wing devices. The relationships of geometry and orientation of the angled segments with bimorph bend-twist response will be presented using results of finite-element analyses.
Piezoelectric Energy Harvesting: In this work, a global air vehicle finite element model employing empirically determined cyclic loads is used to assess the viability of energy harvesting piezoelectric devices for supplemental power generation in lightweight uninhabited aircraft systems (UASs) where the “Owl” all-composite ultralight UAS is used as a candidate proof-of-concept platform. The Owl was developed at the Mississippi State University Raspet Flight Research Laboratory. In the flight test program, strain-time histories were recorded at key locations throughout the wing and fuselage. These measured strains were used in the investigation of practical implementation of energy harvesting piezoelectric materials within the Owl UAS with the intent of harvesting electrical power from structural oscillations of the wings during operation.
Embedded Magnetostrictive Composite NDE Sensors: This research examines the mechanics of delamination and ply variation on the sensing ability for magnetostrictive particles embedded in a carbon fiber reinforced polymer laminate. Analytical models are used to determine how delamination and ply variation affect the mechanical state and magnetic properties of the embedded terfenol-d particles. Numerical models are also used to simulate the effect of delamination and ply variation on the mechanical state. For the analytical method, the mechanical properties observed are the net strain and stress in a local particle section resulting from magnetostriction. The analytical method reveals that the effect of a delamination is to reduce the resistance to particle actuation in a local area, which allows for variation in stress and magnetostriction magnitudes in damaged areas vs. non-damaged areas. This variation in the mechanical state subsequently affects the magnetic permeability, which changes the reluctance in the local particle layer. These results are compared to a numerical model of terfenol-d embedded in carbon fiber reinforced polymer laminate, which reveal a drop in stress and increase in magnetostriction in the delamination region. Finally, these results are projected to experimental results from health monitoring scans of carbon fiber reinforced polymer laminates with varied ply count from 2-14 plies, with delamination.
Dr. Oliver J. Myers is an Assistant Professor of Mechanical Engineering at Mississippi State University. Dr. Myers is a graduate of the University of Maryland Baltimore County for all three degrees of Bachelors, Masters and Doctorate in Mechanical Engineering. Prior to joining MSU, he worked as a Senior Mechanical Engineer at Northrop Grumman Corporation Electronic Systems Division in Baltimore Maryland as an Integrated Product Team Lead and lead engineer on composite material chassis and module designs, micro systems integration, micro-fabrication and manufacturing of electronic assemblies. He has also worked as a design and analysis engineer at the Naval Air Warfare Center working on several military aircraft platforms and as an engineer with the Maryland Department of the Environment developing the analysis code for the vehicle emission inspection program. He has the honor of being selected in the inaugural class of the prestigious Meyerhoff Scholarship Program at UMBC under the mentorship of Dr. Freeman Hrabowski. While working full-time and attending school full- and part-time on alternating semesters, Dr. Myers completed his dissertation focusing on computational modeling and experimentation of smart material driven micro-electro-mechanical systems. He is conducting research in smart material and smart system applications for nano-, micro-, mini- and macro-scale systems, interdisciplinary computational models of mechanical systems and integrated design/analysis/prototyping of mechanical devices and systems
Monday, April 14, 2014
132 Fluor Daniel Building