Giuseppe Rega – författare

The interest of the applied mechanics community in chaotic dynamics of engineering systems has exploded in the last fifteen years, although research activity on nonlinear dynamical problems in mechanics started well before the end of the Eighties. It developed first within the general context of the classical theory of nonlinear oscillations, or nonlinear vibrations, and of the relevant engineering applications. This was an extremely fertile field in terms of formulation of mechanical and mathematical models, of development of powerful analytical techniques, and of understanding of a number of basic nonlinear phenomena. At about the same time, meaningful theoretical results highlighting new solution methods and new or complex phenomena in the dynamics of deterministic systems were obtained within dynamical systems theory by means of sophisticated geometrical and computational techniques. In recent years, careful experimental studies have been made to establish the actual occurrence and observability of the predicted dynamic phenomena, as it is vitally needed in all engineering fields. Complex dynamics have been shown to characterize the behaviour of a great number of nonlinear mechanical systems, ranging from aerospace engineering applications to naval applications, mechanical engineering, structural engineering, robotics and biomechanics, and other areas. The International Union of Theoretical and Applied Mechanics grasped the importance of such complex phenomena in the Eighties, when the first IUTAM Symposium devoted to the general topic of nonlinear and chaotic dynamics in applied mechanics and engineering was held in Stuttgart (1989).

This is the first book which exploits concepts and tools of global nonlinear dynamics for bridging the gap between theoretical and practical stability of systems/structures, and for possibly enhancing the engineering design in macro-, micro- and nano-mechanics.

with also a specific focus on the mechanics of solids and structures, where the biographies of a meaningful number of recognized Italian scholars of mechanics in all areas are also provided, along with testimonials and memories by a few senior people meaningfully involved with AIMETA and Italian mechanics.

The book retraces the history of the Italian Association of Theoretical and Applied Mechanics (AIMETA) since its establishment in 1965. AIMETA is the official Italian association of mechanics adhering to IUTAM (International Union of Theoretical and Applied Mechanics), which organizes and coordinates a meaningful number of research activities, the most important of which are the biennial National Congress and the internationally renowned journal “Meccanica”, published by Springer. Besides collecting and organizing all related important data and information, as far as possible, by distinguishing among the five scientific areas – general mechanics, solids, structures, fluids, machines – encompassed by AIMETA, the history of the association is assumed as a proper perspective to overview the evolution of theoretical and applied mechanics in Italy over about the last fifty years. This is accomplished in the first part of the book. with also a specific focus on the mechanics of solids and structures, where the biographies of a meaningful number of recognized Italian scholars of mechanics in all areas are also provided, along with testimonials and memories by a few senior people meaningfully involved with AIMETA and Italian mechanics. The second part gives an account, although unavoidably incomplete, of recent developments of mechanical sciences in Italy, as reflected also in the activities of AIMETA and with reference to the international context. Contributions by a number of invited senior scholars, still very active, consist of overviews on some scientific themes in the various areas, summaries of achievements of research groups, expressions of research viewpoints, prospects for future developments.

This book presents insights from the IUTAM Symposium on Nonlinear Dynamics for Design of Mechanical Systems Across Different Length/Time Scales.

This book presents insights from the IUTAM Symposium on Nonlinear Dynamics for Design of Mechanical Systems Across Different Length/Time Scales. It covers a diverse array of topics, including applications of parametric amplification and self-excitation, as well as the design and analysis of devices and systems that harness geometric and material nonlinearities. The book features chapters on nonlinear energy transfer, eigenfrequency detection through subharmonic and superharmonic resonances, and the innovative use of nonlinear mode localization. The authors explore dynamic stabilization under high-frequency excitation, the utilization of multimode interactions and nonlinear normal modes, and the application of nonlinear resonance and bifurcation in creating ultrasensitive sensors and high-performance actuators. This book provides a comprehensive record of the symposium's discussions, representing a collective effort to expand our understanding of nonlinear phenomena and its potential to reshape the landscape of mechanical system design.

This is the first book which exploits concepts and tools of global nonlinear dynamics for bridging the gap between theoretical and practical stability of systems/structures, and for possibly enhancing the engineering design in macro-, micro- and nano-mechanics. Addressed topics include complementing theoretical and practical stability to achieve load carrying capacity; dynamical integrity for analyzing global dynamics, for interpreting/predicting experimental behavior, for getting hints towards engineering design; techniques for control of chaos; response of uncontrolled and controlled system/models in applied mechanics and structural dynamics by also considerung the effect of system imperfections; from relatively simple systems to multidimensional models representative of real world applications; potential and expected impact of global dynamics for engineering design.

Nonlinear phenomena should play a crucial role in the design and control of engineering systems and structures as they can drastically change the prevailing dynamical responses. This book covers theoretical and applications-based problems of nonlinear dynamics concerned with both discrete and continuous systems of interest in civil and mechanical engineering. They include pendulum-like systems, slender footbridges, shape memory alloys, sagged elastic cables and non-smooth problems.Pendulums can be used as a dynamic absorber mounted in high buildings, bridges or chimneys. Geometrical nonlinearities introduced by pendulum motion may change the system dynamics, and entail a rapid increase of the oscillations of both the structure and the pendulum, leading to full pendulum rotation or chaotic dynamics. To magnetorheological damping is proposed.Nonlinear mechanics has to be used to explain undesired response in slender footbridges, such as that occurred in the famous event of the London Millenium Bridge. The observed phenomena can be explained by an analytical nonlinear discrete-time model. Shape memory alloys (SMAs) exhibit very interesting nonlinear thermo-mechanical properties such as shape memory effect and superelasticity. SMA elements integrated within composite beams or plates can be used for active modification of structure properties e.g. by affecting their natural frequencies. Finite amplitude, resonant, forced dynamics of sagged, horizontal or inclined, elastic cables have recently undergone meaningful research advances concerned with modelling, analysis, response, and nonlinear/nonregular phenomena. A variety of features of nonlinear multimodal interaction in different resonance conditions are comparatively addressed. Non-smooth systems are very common in engineering practice. Three mechanical engineering problems are presented: (i) a vibro-impact system in the form of a moling device, (ii) the influence of the opening and closing of a fatigue crack on the host system dynamics, and (iii) nonlinear interactions between a rotor and snubber ring system.  This book is aimed at a wide audience of engineers and researchers working in the field of nonlinear structural vibrations and dynamics, and undergraduate and postgraduate students reading mechanical, aerospace and civil engineering.

Nonlinear dynamics has been enjoying a vast development for nearly four decades resulting in a range of well established theory, with the potential to significantly enhance performance, effectiveness, reliability and safety of physical systems as well as offering novel technologies and designs. By critically appraising the state of the art, it is now time to develop design criteria and technology for new generation products/processes operating on principles of nonlinear interaction and in the nonlinear regime, leading to more effective, sensitive, accurate, and durable methods than what is currently available. This new approach is expected to radically influence the design, control and exploitation paradigms, in a magnitude of contexts. With a strong emphasis on experimentally calibrated and validated models, contributions by top-level international experts will foster future directions for the development of engineering technologies and design using robust nonlinear dynamics modelling and analysis.

The interest of the applied mechanics community in chaotic dynamics of engineering systems has exploded in the last fifteen years, although research activity on nonlinear dynamical problems in mechanics started well before the end of the Eighties. It developed first within the general context of the classical theory of nonlinear oscillations, or nonlinear vibrations, and of the relevant engineering applications. This was an extremely fertile field in terms of formulation of mechanical and mathematical models, of development of powerful analytical techniques, and of understanding of a number of basic nonlinear phenomena. At about the same time, meaningful theoretical results highlighting new solution methods and new or complex phenomena in the dynamics of deterministic systems were obtained within dynamical systems theory by means of sophisticated geometrical and computational techniques. In recent years, careful experimental studies have been made to establish the actual occurrence and observability of the predicted dynamic phenomena, as it is vitally needed in all engineering fields. Complex dynamics have been shown to characterize the behaviour of a great number of nonlinear mechanical systems, ranging from aerospace engineering applications to naval applications, mechanical engineering, structural engineering, robotics and biomechanics, and other areas. The International Union of Theoretical and Applied Mechanics grasped the importance of such complex phenomena in the Eighties, when the first IUTAM Symposium devoted to the general topic of nonlinear and chaotic dynamics in applied mechanics and engineering was held in Stuttgart (1989).

Nonlinear dynamics has been enjoying a vast development for nearly four decades resulting in a range of well established theory, with the potential to significantly enhance performance, effectiveness, reliability and safety of physical systems as well as offering novel technologies and designs. By critically appraising the state of the art, it is now time to develop design criteria and technology for new generation products/processes operating on principles of nonlinear interaction and in the nonlinear regime, leading to more effective, sensitive, accurate, and durable methods than what is currently available. This new approach is expected to radically influence the design, control and exploitation paradigms, in a magnitude of contexts. With a strong emphasis on experimentally calibrated and validated models, contributions by top-level international experts will foster future directions for the development of engineering technologies and design using robust nonlinear dynamics modelling and analysis.