Plenary Lecture

Large Nonlinear Dynamic Responses of Shell Structures with Piezoelectric Sensing and Actuating Layers

Professor Cho W. Solomon To
Co-Author W. Niu
Department of Mechanical and Materials Engineering
University of Nebraska

Abstract: Over the last forty years or so, considerable research effort has been exerted on adaptive structures that based on the application of sensors and actuators. This is, perhaps, due to their useful and potential applications in aerospace, and, to a lesser extent, in shipbuilding as well as automotive engineering industries. Applications of materials such as piezoelectrics, shape memory alloys, and magnetostrictive materials have further been expanded in other fields such as robotics, highway engineering, and biomechanics. Piezoelectrics are perhaps the most widely used of these active materials due mainly to their high stiffnesses and their properties of being easily control through the use of applied voltage or surface charge. Compared with the use of piezoelectrics in transducer fabrications, the control of structural vibration by using distributed actuators and sensors is another important area of active research. In structural vibration control, for example, the relatively complex geometrical configurations of structural systems and nature of physical characteristics of piezoelectrics render analytical methods impossible or infeasible. Therefore, the versatile numerical approach, the finite element method (FEM) has been employed. Since the pioneering work of Allik and Hughes (1970) many publications of linear and nonlinear analysis of structures with piezoelectric properties have been presented. Among these publications various shell finite elements with piezoelectric effects were reported. In particular, the three node triangular shell finite elements with piezoelectric effects presented by the author and his associates (2001, 2003) are good examples. The main features of these three node triangular shell elements are (a) every node has six degrees-of-freedom (dof) and one electric potential dof, (b) hybrid strain-based formulation, (c) element mass and stiffness matrices are explicit in the sense that no numerical matrix inversion and integration are required in their derivations, and (d) one of these shell finite elements can give correctly the six rigid body modes. In the investigation being reported in this presentation, the foregoing features are expanded to include features of large nonlinear dynamic responses of finite strains and finite rotations, thickness updating, and director formulation. The latter feature is of particular importance in cases where large rotational displacements cannot be obtained by non-director formulations. In this presentation, selected computed results are included to demonstrate the aforementioned features.

Brief Biography of the Speaker: Dr. To has obtained his doctoral degree in sound and vibration studies from the University of Southampton in April 1980. He is currently Professor in the Department of Mechanical and Materials Engineering, University of Nebraska, Lincoln, Nebraska, U.S.A. Prior to joining the University of Nebraska he was a professor at the University of Western Ontario, Canada. He was an associate professor at the University of Calgary, Canada before joining the University of Western Ontario. Between 1982-1992 he was a University Research Fellow of the Natural Sciences and Engineering Research Council of Canada. He was a Research Fellow at the Institute of Sound and Vibration Research (ISVR), University of Southampton. Presently, he is a Fellow of the American Society of Mechanical Engineers (ASME). His main interests are in: Nonlinear stochastic structural dynamics; nonlinear finite element analysis with particular reference to laminated composite plates and shells, and piezoelectric shells; nonlinear dynamics, vibration, and control; and mechanics of nano-structures.

Bulletin Board


The Conference Guide is online.

The paper submission deadline has expired. Please choose a future conference to submit your paper.

Plenary Speakers

WSEAS Main Site

Publication Ethics and Malpractice Statement