Preface of the “Symposium on New Methods for Modeling and Control of Flexible Structures and Robots”

The flexible structures and robots are necessary and/or indispensable in: 1. winding and/or very cramped workspaces (where less invasive robots, and therefore with slender links, are required); 2. very wide workspaces or anyway robots with end-effectors very far from their bases, because of the presence of obstacles (rivers, buildings, etc.), or when it is impossible or not convenient to use robots with mobile base or more cooperative robots (e.g. to build and/or to maintain mega-structures, electric lines, etc.); 3. dangerous and/or harmful areas of work both for the human operators and for the actuators with the electronic control (rescue and security robots). For these reasons the modeling and control of robots with flexible links and, more generally, of flexible structures with degrees of freedom, has been a historic topic of research and it remains very interesting and significant for the scientific and engineering community. Nowadays, in fact, in the above mentioned cases higher and higher specifications are required in terms of operating speeds and/or amplitude of areas of work and security; the only way to satisfy the previous specifications is to reduce the mass and to make the structures slender, i.e. to employ articulated structures having flexibility properties. Obviously, in order to reduce the disadvantages due to flexibility (oscillations and/or vibrations, breaking and the spillover phenomenon when the structure is controlled by a closed-loop controller), it is necessary to design advanced control systems based on reliable and efficient models. This Symposium collects several multidisciplinary contributions in the automatic, mechanical, civil, aeronautical and naval sectors giving some significant answers to the above complex matters which remain still open