LA MECCANICA DELLE MACCHINE NELL’INNOVAZIONE DEI PRODOTTI E DEI PROCESSI

Abstract

The present report highlights the current and future role of techniques and methodologies of the Mechanics of Machines, both in the design of devices and systems, and in the university training courses. The underlying theme of the presentation lays in the interpretation of the physical phenomenon which oversees the operation of the machines. This is the foundation allowing to define an input-output interaction between the physical quantities operating on the machine. The cause-effect relation offers the possibility to determine a set of analytical relations for the prediction of the operation of the machine and to simulate theoretical and / or numerical trends in time or frequency domain of the significant mechanical quantities. It is evident the magnitude of the physical phenomena that arise in the operation of a machine, resulting in a broad variety of related Mechanics of Machines topics: from the contact between bodies analysis to tribological aspects, from body geometry to kinematics, from the rigid to deformable body dynamics, from the interaction between mechanical bodies to manmachine interaction, from the kinematic and dynamic behavior of a mechanical system to its interface with the actuators, sensing and control, just to name some of them. It should also be considered that the interpretation of the physical phenomenon of organs of machines has to be supported by significant experimental campaigns, specifically reproduced in laboratory, or related to data from real applications in the different application domains. The evolution of Mechanics of Machines proved in the years to be able to respond to these two interacting and converging questions: on the one hand the need to identify analytical relations, possibly not based on sole mappings of data, but rather on representative analytical relations of physical quantities, and on the other hand, the need, even at the university level, to conduct appropriate laboratory test campaigns related to the real field operation of the machine. With reference to the first objective, the need to determine algorithms, typically non-linear, and the consequent simulations setups, has resulted in the passage of the Machine Mechanics from a theoretical subject, to a subject with strong computational valences creating tools for the prediction of the behavior of devices and systems, in relation to their diagnosis and health state. The second objective has required the achievement of competence also in the field of the test rigs, of sensing and measuring / data acquisition systems. The paper deals with the identification and the presentation of the different areas related to Machine Mechanics, exposing in a matrix the enabling technologies on the one hand and the application domains to which they apply in the other hand. The enabling technologies traditionally belong to the topics of kinematics, statics, dynamics (linear and nonlinear), to the interactions with the environment (force fields, interactions with fluids) and between surfaces (lubrication), control, automation and system identification, as well as to the study and identification of vibratory phenomena, vibro-acoustic and tribological ones, mechatronics, fluid-structure interactions, monitoring, diagnostics and prognostics of mechanical systems, fluid automation and robotics, fluidics and microfluidics, to the implementation of pneumatic, hydraulic, electric and non-conventional technologies, to environmentally friendly and renewable energy systems. The application domains relate to the mechanical systems, such as driving and operating machinery, mechanical devices, mechanisms, transmissions and drives, automatic and robotic, vehicles on road, rail, fixed wing and rotorcrafts, transportation and lifting systems, systems for the production of energy, the biomechanical systems. A summary of the ongoing activities in the different research groups of the Italian Universities is then presented, from which you can also highlight the methodology of the studies addressed, strongly aimed at a unifying approach through the use of fundamental methods of theoretical applied and experimental mechanics, with attention to environmental and energy sustainability, and significantly connected on one side with the state of international research, and on the other with the industrial and manufacturing reality of the country. At the end of the paper sectors of Machine Mechanics that in the opinion of the writer need to be investigated further are discussed. Some technological challenges, such as prognostic models applied to servo systems in primary flight controls for aircraft applications, are outlined. The state of the art in that domain highlights the contribution to the innovation of processes and products, challenge that need to go back to the inputoutput interactions at the base-mechanics layer. Without those aspects it is impossible to be able to predict the evolution of degradation in the actuation systems, and to determine the remaining life of a mechanical device.