Active Control Of Noise And Vibration

Integrating active control of both sound and vibration, this comprehensive two-volume set combines coverage of fundamental principles with the most recent theoretical and practical developments. The authors explain how to design and implement successful active control systems in practice and detail the pitfalls one must avoid to ensure a reliable and stable system. Extensively revised, updated, and expanded throughout, the second edition reflects the advances that have been made in algorithms, DSP hardware, and applications since the publication of the first edition.

This major work is the first to treat the active control of both sound and vibration in a unified way. It outlines the fundamental concepts, explains how a reliable and stable system can be designed and implemented, and details the pitfalls . It covers sound in ducts, sound radiation, sound transmission into enclosures, structural vibration and isolation, electronic control system design, and sensors and actuators.

This book is a companion text to Active Control of Sound by P.A. Nelson and S.J. Elliott, also published by Academic Press. It summarizes the principles underlying active vibration control and its practical applications by combining material from vibrations, mechanics, signal processing, acoustics, and control theory. The emphasis of the book is on the active control of waves in structures, the active isolation of vibrations, the use of distributed strain actuators and sensors, and the active control of structurally radiated sound. The feedforward control of deterministic disturbances, the active control of structural waves and the active isolation of vibrations are covered in detail, as well as the more conventional work on modal feedback. The principles of the transducers used as actuateors and sensors for such control strategies are also given an in-depth description. The reader will find particularly interesting the two chapters on the active control of sound radiation from structures: active structural acoustic control. The reason for controlling high frequency vibration is often to prevent sound radiation, and the principles and practical application of such techniques are presented here for both plates and cylinders. The volume is written in textbook style and is aimed at students, practicing engineers, and researchers. Combines material from vibrations, signal processing, mechanics, and controls Summarizes new research in the field

Noise and Vibration Control Engineering: Principles and Applications, Second Edition is the updated revision of the classic reference containing the most important noise control design information in a single volume of manageable size. Specific content updates include completely revised material on noise and vibration standards, updated information on active noise/vibration control, and the applications of these topics to heating, ventilating, and air conditioning.

Control of Noise and Structural Vibration presents a MATLAB®-based approach to solving the problems of undesirable noise generation and transmission by structures and of undesirable vibration within structures in response to environmental or operational forces. The fundamentals of acoustics, vibration and coupling between vibrating structures and the sound fields they generate are introduced including a discussion of the finite element method for vibration analysis. Following this, the treatment of sound and vibration control begins, illustrated by example systems such as beams, plates and double walls. Sensor and actuator placement is explained as is the idea of modal sensor–actuators. The design of appropriate feedback systems includes consideration of basic stability criteria and robust active structural acoustic control. Positive position feedback (PPF) and multimode control are also described in the context of loudspeaker–duct and loudspeaker–microphone models. The design of various components is detailed including the analog circuit for PPF, adaptive (semi-active) Helmholtz resonators and shunt piezoelectric circuits for noise and vibration suppression. The text makes extensive use of MATLAB® examples and these can be simulated using files available for download from the book’s webpage at springer.com. End-of-chapter exercises will help readers to assimilate the material as they progress through the book. Control of Noise and Structural Vibration will be of considerable interest to the student of vibration and noise control and also to academic researchers working in the field. It’s tutorial features will help practitioners who wish to update their knowledge with self-study.

Since the publication of the first edition, considerable progress has been made in the development and application of active noise control (ANC) systems, particularly in the propeller aircraft and automotive industries. Treating the active control of both sound and vibration in a unified way, this second edition of Active Control of Noise and Vibration continues to combine coverage of fundamental principles with the most recent theoretical and practical developments. What's New in This Edition Revised, expanded, and updated information in every chapter Advances in feedforward control algorithms, DSP hardware, and applications Practical application examples of active control of noise propagating in ducts The use of a sound intensity cost function, model reference control, sensing radiation modes, modal filtering, and a comparison of the effectiveness of various sensing strategies New material on feedback control of sound transmission into enclosed spaces New material on model uncertainty, experimental determination of the system model, optimization of the truncated model, collocated actuators and sensors, biologically inspired control, and a discussion of centralised versus de-centralised control A completely revised chapter on control system implementation New material on parametric array loudspeakers, turbulence filtering, and virtual sensing More material on smart structures, electrorheological fluids, and magnetorheological fluids Integrating the related disciplines of active noise control and active vibration control, this comprehensive two-volume set explains how to design and implement successful active control systems in practice. It also details the pitfalls one must avoid to ensure a reliable and stable system.

Since the publication of the first edition, considerable progress has been made in the development and application of active noise control (ANC) systems, particularly in the propeller aircraft and automotive industries. Treating the active control of both sound and vibration in a unified way, this second edition of Active Control of Noise and Vibration continues to combine coverage of fundamental principles with the most recent theoretical and practical developments. What's New in This Edition Revised, expanded, and updated information in every chapter Advances in feedforward control algorithms, DSP hardware, and applications Practical application examples of active control of noise propagating in ducts The use of a sound intensity cost function, model reference control, sensing radiation modes, modal filtering, and a comparison of the effectiveness of various sensing strategies New material on feedback control of sound transmission into enclosed spaces New material on model uncertainty, experimental determination of the system model, optimization of the truncated model, collocated actuators and sensors, biologically inspired control, and a discussion of centralised versus de-centralised control A completely revised chapter on control system implementation New material on parametric array loudspeakers, turbulence filtering, and virtual sensing More material on smart structures, electrorheological fluids, and magnetorheological fluids Integrating the related disciplines of active noise control and active vibration control, this comprehensive two-volume set explains how to design and implement successful active control systems in practice. It also details the pitfalls one must avoid to ensure a reliable and stable system.

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.

Two of the most acclaimed reference works in the area of acoustics in recent years have been our Encyclopedia of Acoustics, 4 Volume set and the Handbook of Acoustics spin-off. These works, edited by Malcolm Crocker, positioned Wiley as a major player in the acoustics reference market. With our recently published revision of Beranek & Ver's Noise and Vibration Control Engineering, Wiley is a highly respected name in the acoustics business. Crocker's new handbook covers an area of great importance to engineers and designers. Noise and vibration control is one largest areas of application of the acoustics topics covered in the successful encyclopedia and handbook. It is also an area that has been under-published in recent years. Crocker has positioned this reference to cover the gamut of topics while focusing more on the applications to industrial needs. In this way the book will become the best single source of need-to-know information for the professional markets.

This book describes modern techniques for reducing the level of airborne noise through the introduction of sound radiated by additional secondary sources, bringing together the results of contemporary research in this area. It is the combination of the physical properties of sound fields and modern digital signal processing technology that has made the active control of sound a practical proposition in a number of important applications. The book covers both these aspects of the subject, initially at a fundamental level, and then in detail in later chapters. The structure of the book is such that it should be suitable for both those seeking a basic understanding of the subject and as a reference for researchers in the field. A key feature of the work is the unified presentation of material from the two disciplines of acoustics and signal processing.