Piezoelectric Transducers For Vibration Control And Damping

This book presents recent developments in vibration control systems that employ embedded piezoelectric sensors and actuators, reviewing ways in which active vibration control systems can be designed for piezoelectric laminated structures, paying distinct attention to how such control systems can be implemented in real time. Includes numerous examples and experimental results obtained from laboratory-scale apparatus, with details of how similar setups can be built.

Self sensing techniques allow using a piezoelectric transducer simultaneously as an actuator and as a sensor, as they reconstruct its mechanical sensory information by measuring its electrical quantities, i.e. voltage and charge. In vibration control applications piezoelectric self sensing actuators are highly desirable as they allow precise collocated control. Past research work was mainly based on the linear behavior of piezoelectric materials, thus restricting the operating driving voltages to low values. This work addresses the problem of using a self sensing piezoelectric actuator at its full driving voltage range. A new self sensing technique is proposed, which is based on the hysteretic modeling and identification of the piezoelectric transducer capacitance. After providing a sound presentation on piezoelectricity and vibrating structures, the most common self sensing techniques are discussed and the new self sensing technique is introduced and compared to typical linear methods both theoretically and experimentally.

“Piezoelectric-Based Vibration-control Systems: Applications in Micro/Nano Sensors and Actuators” covers: Fundamental concepts in smart (active) materials including piezoelectric and piezoceramics, magnetostrictive, shape-memory materials, and electro/magneto-rheological fluids; Physical principles and constitutive models of piezoelectric materials; Piezoelectric sensors and actuators; Fundamental concepts in mechanical vibration analysis and control with emphasis on distributed-parameters and vibration-control systems; and Recent advances in piezoelectric-based microelectromechanical and nanoelectromechanical systems design and implementation.

This text is an introduction to the dynamics of active structures and to the feedback control of lightly damped flexible structures; the emphasis is placed on basic issues and simple control strategies that work. Now in its third edition, more chapters have been added, and comments and feedback from readers have been taken into account, while at the same time the unique premise of bridging the gap between structure and control has remained. Many examples and problems bring the subject to life and take the audience from theory to practice. The book has chapters dealing with some concepts in structural dynamics; electromagnetic and piezoelectric transducers; piezoelectric beam, plate and truss; passive damping with piezoelectric transducers; collocated versus non-collocated control; active damping with collocated systems; vibration isolation; state space approach; analysis and synthesis in the frequency domain; optimal control; controllability and observability; stability; applications; tendon control of cable structures; active control of large telescopes; and semi-active control. The book concludes with an exhaustive bibliography and index. This book is intended for structural engineers who want to acquire some background in vibration control; it can be used as a textbook for a graduate course on vibration control or active structures. A solutions manual is available through the publisher to teachers using this book as a textbook.

Vibration is a natural phenomenon that occurs in a variety of engineering systems. In many circumstances, vibration greatly affects the nature of engineering design as it often dictates limiting factors in the performance of the system. The conventional treatment is to redesign the system or to use passive damping. The former could be a costly exercise, while the latter is only effective at higher frequencies. Active control techniques have emerged as viable technologies to fill this low-frequency gap. This book is concerned with the study of feedback controllers for vibration control of flexible structures, with a view to minimizing vibration over the entire body of the structure.The book introduces a variety of flexible structures such as beams, strings, and plates with specific boundary conditions, and explains in detail how a spatially distributed model of such systems can be obtained. It addresses the problems of model reduction and model correction for spatially distributed systems of high orders, and goes on to extend robust control techniques such as H-infinity and H2 control design methodologies to spatially distributed systems arising in active vibration control problems. It also addresses other important topics, such as actuator and sensor placement for flexible systems, and system identification for flexible structures with irregular boundary conditions. The text contains numerous examples, and experimental results obtained from laboratory-level apparatus, with details of how similar test beds may be built.

The piezoelectric transducer converts electric signals into mechanical vibrations or vice versa by utilizing the morphological change of a crystal which occurs on voltage application, or conversely by monitoring the voltage generated by a pressure applied on a crystal. This book reports on the state of the art research and development findings on this very broad matter through original and innovative research studies exhibiting various investigation directions. The present book is a result of contributions of experts from international scientific community working in different aspects of piezoelectric transducers. The text is addressed not only to researchers, but also to professional engineers, students and other experts in a variety of disciplines, both academic and industrial seeking to gain a better understanding of what has been done in the field recently, and what kind of open problems are in this area.

My objective in writing this book was to cross the bridge between the structural dynamics and control communities, while providing an overview of the potential of SMART materials for sensing and actuating purposes in active vibration c- trol. I wanted to keep it relatively simple and focused on systems which worked. This resulted in the following: (i) I restricted the text to fundamental concepts and left aside most advanced ones (i.e. robust control) whose usefulness had not yet clearly been established for the application at hand. (ii) I promoted the use of collocated actuator/sensor pairs whose potential, I thought, was strongly underestimated by the control community. (iii) I emphasized control laws with guaranteed stability for active damping (the wide-ranging applications of the IFF are particularly impressive). (iv) I tried to explain why an accurate pred- tion of the transmission zeros (usually called anti-resonances by the structural dynamicists) is so important in evaluating the performance of a control system. (v) I emphasized the fact that the open-loop zeros are more difficult to predict than the poles, and that they could be strongly influenced by the model trun- tion (high frequency dynamics) or by local effects (such as membrane strains in piezoelectric shells), especially for nearly collocated distributed actuator/sensor pairs; this effect alone explains many disappointments in active control systems.

These proceedings of the Third European Workshop on Structural Health Monitoring held at the Conference Centre in Granada, Spain, in July of 2006 includes four keynote presentations and 170 technical papers written by an international group of contributors. Papers discuss technology and activities related to damage detection and evaluation in engin