Introduction To Dynamics And Control Of Flexible Structures

This book addresses problems in structural dynamics and control encountered in applications such as robotics, aerospace structures, earthquake-damage prevention, and active noise suppression. The rapid developments of new technologies and computational power have made it possible to formulate and solve engineering problems that seemed unapproachable only a few years ago. This presentation combines concepts from control engineering (such as system norms and controllability) and structural engineering (such as modal properties and models), thereby revealing new structural properties as well as giving new insight into well-known laws. This book will assist engineers in designing control systems and dealing with the complexities of structural dynamics.

Flexible structures arise in significant important areas of application, such as robotics, large space structures, and antenna control. Difficulties related to sensing and identification hamper control of such systems. These problems require collaboration between mathematicians and engineers. To promote such collaboration, the Fields Institute sponsored a three-day workshop entitled ``Problems in Sensing, Identification, and Control of Flexible Structures'' in June 1992. This volume contains papers presented at the workshop. Topics range from theoretical research on the well-posedness of systems, to experimental implementations of various controllers. A number of controller design techniques are discussed and compared, and there are several papers on modelling the complex dynamics of flexible structures. This book is a useful resource to control theorists, engineers, and mathematicians interested in this important field of research.

A text/reference on analysis of structures that deform in use. Presents a new, integrated approach to analytical dynamics, structural dynamics and control theory and goes beyond classical dynamics of rigid bodies to incorporate analysis of flexibility of structures. Includes real-world examples of applications such as robotics, precision machinery and aircraft structures.

Methods of structural control and dynamics are introduced in this book. These include reduction of large structural models by balanced truncation, placement of actuators and sensors for dynamic testing and control, structural identification of the minimum-order balanced representation, balanced dissipative controller design, balanced LQG and H( controller designs with the closed-form relationships between controller parameters and system performance, and controller reduction methods that preserve the closed-loop performance. The book explores the unique properties of flexible structures to obtain efficient methods of dynamic analysis and controller design. The presented methods of structural dynamics, identification, sensor/actuator placement, and passive, LQG and H( controller design have been checked both with simulations and industrial implementations.

This book is concerned with electrostructural systems, particularly the interaction between the control of the structural and electrical (electronic) components. Structronics is a new emerging area with many potential applications in the design of high-performance structures, adaptive structures, high-precision systems, and micro-systems. As structures are increasingly being controlled by electronics, the problems of structural engineering can be separated less and less from those of electronic engineering and control engineering. This graduate-level book fills a gap in the literature by considering these problems while giving an overview of the current state of analysis, modelling and control for structronic systems. It is a coherent compendium written by leading experts in this new research area and gives readers a sophisticated toolbox that will allow them to tackle the modelling and control of smart structures. The inclusion of an extensive, up-to-date bibliography and index makes this volume an invaluable standard for professional reference. Because of the large number of contributions to the present volume, it has been subdivided into two parts, of which this is Part I. This book will be of interest to engineers, materials scientists, physicists and applied mathematicians. The synergistic integration of active (smart) materials, structures, sensors, actuators, and control electronics has redefined the concept of structures from a conventional passive elastic system to an active (life-like) structronic (structure + electronic) system with inherent self-sensing, diagnosis, and control capabilities. Because of its multi-disciplinary nature, the development of structronic systems has attracted researchers and scientists from many disciplines, such as structures, materials, control, electronics, mathematics, manufacturing, electromechanics, and mechanics. In practical applications, this new structronic system can be used as a component of high-performance machines or structural systems, or be an integrated structure itself performing designated function(s). Most common active (smart) materials, such as piezoelectrics, shape-memory alloys, electro- and magneto-strictive materials, and polyelectrolyte gels have been reviewed in Part I. Application examples are also provided and research issues reported on. While the first part focuses primarily on materials and structures, Part II emphasizes control applications and intelligent systems. With the information provided in this two-volume book, scientists and researchers can easily grasp the state of the art of smart materials and structronic systems, and are ready to pursue their own research and development endeavors. Contents:Part I: Materials and StructuresThe Piezoelectric Vibration Absorber Systems (J Holkamp & T Starchville, Jr.)Self-Sensing Control Applied to Smart Material Systems (E Garcia & L D Jones)An Introduction to Active Constrained Layer Damping Treatments (S Shen)Static and Dynamic Behavior of Adaptive Wings Carrying Externally Mounted Stores (L Librescu & O Song)Adaptive Design and Active Composite Material Systems (J Tani & J-H Qiu)Microelectromechanics and Functionality of Segmented Cylindrical Transducers (H-S Tzou et al.)Thermomechanical Modeling of Shape Memory Alloys and Composites (D Lagoudas et al.)Active-Passive Hybrid Structural Vibration Controls Via Piezoelectrical Networks (K-W Wang & S Kahn)On-Line Structural Damage Detection (H Shen)On Material Degradation and Failure of Piezoelectric Ceramics (H Sosa)Part II: Systems and ControlNear-Minimum-Time Slewing and Vibration Control of Smart Structures(Y Kim et al.)Active Polyelectrolyte Gels as Electrically Controllable Artificial Muscles and Intelligent Network Structures(M Shahinpoor)Active Dynamic Absorbers — Theory and Application(S Tewani et al.)Active Vibration Sink for Flexible Structures(C-S Chou)Distributed Modal-Space Control and Estimation with Electroelastic Applications(H Öz)Markov Parameters in System Identification: Old and New Concepts(M Q Phan et al.)Effect of System Non-Linearities on the Modified Model Reference Adaptive Control Scheme(H M Sardar & M Ahmadian)Extending Teach-Repeat to Nonholonomic Robots(S B Skaar & J-D Yoder)Dynamic Analysis and Active Vibration Control of Chain Drive Systems(C-A Tan et al.)Basic Concepts of Fault-Tolerant Computing Design(C Aktouf et al.) Readership: Applied mathematicians, applied physicists and mechanical engineers. Keywords:Structronic Systems;Smart Structures;Devices;Systems;Materials;ControlReviews: “… Professors Guran and Tzou coined the word Structronics in the early 1990s as a new discipline describing the synergetic integration of active materials, structures, sensors, actuators, and control electronics. The present two-volume set is the first comprehensive book ever published on this newly emerging area of engineering. I believe anyone who would like to know what modern science and technology can offer for the design of better structures can learn a great deal from this book. Students and educators can use it as supplemental reading in an intermediate or advanced course on Structronics, or to gain a broader knowledge of systems thinking, model materials, and structural systems. Practicing engineers wishing to consolidate their knowledge in smart technology will also find this book an invaluable reference.” Dr Bernd Schaefer Director Institute of Robotics and Mechatronics, Wessling, Germany

Methods of structural control and dynamics are introduced in this book. These include reduction of large structural models by balanced truncation, placement of actuators and sensors for dynamic testing and control, structural identification of the minimum-order balanced representation, balanced dissipative controller design, balanced LQG and H( controller designs with the closed-form relationships between controller parameters and system performance, and controller reduction methods that preserve the closed-loop performance. The book explores the unique properties of flexible structures to obtain efficient methods of dynamic analysis and controller design. The presented methods of structural dynamics, identification, sensor/actuator placement, and passive, LQG and H( controller design have been checked both with simulations and industrial implementations.