Engineering Commons^™

Vibrating Flexoelectric Micro-Beams As Angular Rate Sensors, Yilin Qu, Feng Jin, Jiashi S. Yang

Department of Mechanical and Materials Engineering: Faculty Publications

We studied flexoelectrically excited/detected bending vibrations in perpendicular directions of a micro-beam spinning about its axis. A set of one-dimensional equations was derived and used in a theoretical analysis. It is shown that the Coriolis effect associated with the spin produces an electrical output proportional to the angular rate of the spin when it is small. Thus, the beam can be used as a gyroscope for angular rate sensing. Compared to conventional piezoelectric beam gyroscopes, the flexoelectric beam proposed and analyzed has a simpler structure.

Vibrating Flexoelectric Micro-Beams As Angular Rate Sensors, Yilin Qu, Feng Jin, Jiashi S. Yang

Department of Mechanical and Materials Engineering: Faculty Publications

We studied flexoelectrically excited/detected bending vibrations in perpendicular directions of a micro-beam spinning about its axis. A set of one-dimensional equations was derived and used in a theoretical analysis. It is shown that the Coriolis effect associated with the spin produces an electrical output proportional to the angular rate of the spin when it is small. Thus, the beam can be used as a gyroscope for angular rate sensing. Compared to conventional piezoelectric beam gyroscopes, the flexoelectric beam proposed and analyzed has a simpler structure.

Vibration And Buckling Of Carbon Nanotube, Graphene, And Nanowire, Mohammad Hadi Mahdavi

Electronic Thesis and Dissertation Repository

Nanostructured materials with superior physical properties hold promise for the development of novel nanodevices. Full potential applications of such advanced materials require accurate characterization of their physical properties, which in turn necessitates the development of computer-based simulations along with novel experimental techniques. Since controlled experiments are difficult for nanoscale materials and atomic studies are computationally expensive, continuum mechanics-based simulations of nanomaterials and nanostructures have become the focal points of computational nano-science and materials modelling.

In this study, emphasis is given to predicting the mechanical behaviour of carbon nanotube (CNT), graphene, nanowire (NW), and nanowire encapsulated in carbon nanotube (NW@CNT), which …

Characterization Of Conducting-Polymer-Based Bimorph Vibration Sensors, Weihua Li, Geoffrey M. Spinks, Lianbin Zhao, Yanzhe Wu, Dezhi Zhou, G G. Wallace

Professor Weihua Li

This paper presents theoretical and experimental investigation of mechanical-electrical properties of conducting polymers based bimorph sensors. A material parameter, hCP , is proposed to represent linear relationship between induction charge and the applied external deformation. Based on this assumption, a constitutive equation for bimorph sensors under steady-state external loadings are constructed and then solved. Mechanical-electrical properties of bimorph sensors are experimentally studied using both vibration-amplitude sweep mode and frequency sweep mode. The material parameter hCP , is identified by comparing theoretical analysis and experimental results. The applications of conducting polymers based bimorph sensors in smart structures are also discussed.

Vibration Of Carbon Nano-Structures, Sina Arghavan

Electronic Thesis and Dissertation Repository

In this thesis, first the fundamental characterizations of carbon nano-structures and basic atomistic models of the carbon nanotubes and graphitic sheets are reviewed extensively. Different simulation methods used in this field of study are discussed critically. Advantages and shortfalls of each method are reported in detail. A new structural approach based on the lattice atomic structure is selected as an accurate and efficient model for simulating carbon nano-structures. This method is used comprehensively in the present work along with continuous shell and plate theories to study the mechanical and vibrational characteristics of single-walled carbon nanotubes and single and multi-layered graphene …