Iutam Symposium On Interaction Between Dynamics And Control In Advanced Mechanical Systems

During the last decades, applications of dynamical analysis in advanced, often nonlinear, engineering systems have been evolved in a revolutionary way. In this context one can think of applications in aerospace engineering like satellites, in naval engineering like ship motion, in mechanical engineering like rotating machinery, vehicle systems, robots and biomechanics, and in civil engineering like earthquake dynamics and offshore technology. One could continue with this list for a long time. The application of advanced dynamics in the above fields has been possible due to the use of sophisticated computational techniques employing powerful concepts of nonlinear dynamics. These concepts have been and are being developed in mathematics, mechanics and physics. It should be remarked that careful experimental studies are vitally needed to establish the real existence and observability of the predicted dynamical phenomena. The interaction between nonlinear dynamics and nonlinear control in advanced engineering systems is becoming of increasing importance because of several reasons. Firstly, control strategies in nonlinear systems are used to obtain desired dynamic behaviour and improved reliability during operation, Applications include power plant rotating machinery, vehicle systems, robotics, etc. Terms like motion control, optimal control and adaptive control are used in this field of interest. Since mechanical and electronic components are often necessary to realize the desired action in practice, the engineers use the term mechatronics to indicate this field. If the desired dynamic behaviour is achieved by changing design variables (mostly called system parameters), one can think of fields like control of chaos.

This volume contains selected papers presented at the Symposium on "Recent Developments in Non-linear Oscillations of Mechanical Systems", held in Hanoi, Vietnam, from 2 - 5 March 1999. This Symposium was initiated and sponsored by the International Union of Theoretical and Applied Mechanics (lUI AM) and organised in conjunction with Vietnam National University, Hanoi. Ihe purpose of the Symposium was to bring together scientists active in different fields of oscillations with the aim to review the recent progress in theory of oscillations and engineering applications and to outline the prospects in its further achievements to then co-ordinate and direct research in this field to further co-operation between scientists and various scientific institutions. An International Scientific Committee was appointed by the Bureau of IUI AM with the following members: Nguyen Van Dao (Vietnam, Co-Chairman) E.J. Kreuzer (Germany, Co-Chairman) D.H. van Campen (The Netherlands) F.L. Chernousko (Russia) A.H. Nayfeh (U.S.A) Nguyen Xuan Hung (Vietnam) W.O. Schiehlen (Germany) J.M.T. Thompson (U.K) Y. Veda (Japan). This Committee selected the participants to be invited and the papers to be presented at the Symposium. As a result of this procedure, 52 active scientists from 16 countries responded to the invitation, and 42 papers were presented in lecture and poster discussion sessions.

This book presents the latest research results in the area of applied nonlinear dynamics and chaos theory. Papers by three academic generations address new applications of nonlinear dynamics to mechanics, including fluid-structure interaction, machining and mechanics of solids, and many other applications.

This book is a collection of selected reviewed papers that were presented at the International Union of Theoretical and Applied Mechanics Symposium "Mechanical waves for composite structures characterization". The Symposium took place June 14-17, 2000 in Chania, Crete, Greece. As is customary, IUTAM Symposia Proceedings are published in the series "Solid Mechanics and Its Applications" by Kluwer Academic Publishers. I am indebted to Professor G. M. L. Gladwell who is the series editor. I would also like to take this opportunity to express my sincere gratitude to Professor M. A. Hayes the Secretary General of the International Union of Theoretical and Applied Mechanics and a member ofthe Symposium's Scientific Committee. His constant encouragement and support made the Symposium not only possible but also successful. To the success also contributed all the members of the Symposium's Scientific Committee which I had the honor to chair. I express my appreciation to each one of them who are: Professor J. D. Achenbach (Northwestern University, Evanston, Illinois, USA), Professor M. A. Hayes (University College, Dublin, Ireland), Professor K. J. Langenberg (University of Kassel, Germany), Professor A. K. Mal (University of California, Los Angeles, USA), Professor X. Markenscoff (University of California, San Diego, USA), Professor S. Nair (Illinois Institute of Technology, Chicago, USA), Professor R. W. Ogden (University of Glasgow, UK), Professor G.

Rapid developments in nonlinear dynamics and chaos theory have led to publication of many valuable monographs and books. However, most of these texts are devoted to the classical nonlinear dynamics systems, for example the Duffing or van der Pol oscillators, and either neglect or refer only briefly to systems with motion-dependent discontinuities. In engineering practice a good part of problems is discontinuous in nature, due to either deliberate reasons such as the introduction of working clearance, and/or the finite accuracy of the manufacturing processes. The main objective of this volume is to provide a general methodology for describing, solving and analysing discontinuous systems. It is compiled from the dedicated contributions written by experts in the field of applied nonlinear dynamics and chaos. The main focus is on mechanical engineering problems where clearances, piecewise stiffness, intermittent contact, variable friction or other forms of discontinuity occur. Practical applications include vibration absorbers, percussive drilling of hard materials and dynamics of metal cutting. Contents:PreliminariesMathematical Models of Mechanical Systems with DiscontinuitiesTemporal and Spatial Discontinuity TransformationsExtensions of Cell Mapping for Discontinuous SystemsImpact OscillatorDynamics of Piecewise Linear OscillatorsQuenching of Self-Excited Vibrations by Impact DamperDynamic Phenomena in Gear BoxesRigorous Methods and Numerical Results for Dry Friction ProblemsForced Self-Excited Vibration with Dry FrictionStick–Slip and the Phase-Space ReconstructionMultidegree of Freedom Systems with Dry FrictionDynamic Instabilities in Spinning DisksImpacts and Dry FrictionNonlinear Dynamics of Orthogonal Metal CuttingDynamics of Ultrasonic Drilling of Hard Materials Readership: Mechanical engineers. keywords:Nonlinear Dynamics;Discontinuity;Mechanical System;Impacts;Dry Friction;Applications;Chaos “… this volume provides readers with an excellent treatment of such discontinuous systems and can be a good source of ideas to attack those systems effectively … one is immediately obliged to recognize that it is in fact a series of fifteen jewels, which one would hardly find in the relevant more mathematically oriented literature.” Mathematical Reviews

A systematic treatment, based on Green's functions and integral equations, is given to the analytical and numerical methods and results for a great number of 3-D contact problems for elastic bodies. Semi-bounded elastic bodies (layer, cylinder, space with cylindrical or spherical cavity, 3-D wedge, special cases of which are half- and quarter-spaces, cone) and finite elastic bodies (circular plate, finite cylinder, spherical layer, spherical lens, sphere) are considered. Methods introduced in the book can also be applied in fracture mechanics, hydrodynamics, electrostatics, thermodynamics and diffusion theory, continuum mechanics, and mathematical physics, as well as by engineers and students in mathematics, mechanics, and physics.

The IUTAM Symposium on Mechanical and Electromagnetic Waves in Structured Media took place at the University of Sydney from January 18- 22, 1999. It brought together leading researchers from eleven countries for a week-long meeting, with the aim of providing cross-links between the com- nities studying related problems involving elastic and electromagnetic waves in structured materials. After the meeting, participants were invited to submit articles based on their presentations, which were refereed and assembled to constitute these Proceedings. The topics covered here represent areas at the forefront of research intoelastic and electromagnetic waves. They include effect of nonlinearity, diffusion and multiple scattering on waves, as well as asymptotic and numerical techniques. Composite materials are discussed in depth, with example systems ranging fromdusty plasmas to a magneto-elastic microstructured system. Also included are studies of homogenisation, that field which seeks to determine equivalent homogeneous systems which can give equivalent wave properties to structured materials, and inverse problems, in which waves are used as a probe to infer structural details concerning scattering systems. There are also strong groups of papers on the localization of waves by random systems, and photonic and phononic band gap materials. These are being developed by analogue with semiconductors for electrons, and hold out the promise of enabling designers to control the propagation of waves through materials in novel ways. We would like to thank the other members of the Scientific Committee (A.

This textbook deals with optimization of dynamic systems. The motivation for undertaking this task is as follows: There is an ever increasing need to produce more efficient, accurate, and lightweight mechanical and electromechanical de vices. Thus, the typical graduating B.S. and M.S. candidate is required to have some familiarity with techniques for improving the performance of dynamic systems. Unfortunately, existing texts dealing with system improvement via optimization remain inaccessible to many of these students and practicing en gineers. It is our goal to alleviate this difficulty by presenting to seniors and beginning graduate students practical efficient techniques for solving engineer ing system optimization problems. The text has been used in optimal control and dynamic system optimization courses at the University of Deleware, the University of Washington and Ohio University over the past four years. The text covers the following material in a straightforward detailed manner: • Static Optimization: The problem of optimizing a function that depends on static variables (i.e., parameters) is considered. Problems with equality and inequality constraints are addressed. • Numerical Methods: Static Optimization: Numerical algorithms for the solution of static optimization problems are presented here. The methods presented can accommodate both the unconstrained and constrained static optimization problems. • Calculus of Variation: The necessary and sufficient conditions for the ex tremum of functionals are presented. Both the fixed final time and free final time problems are considered.