Estudo de um dispositivo de mola inteligente com acoplamento por atrito para controle semiativo de vibração

Abstract

It is known that vibration control in mechanical systems is a very important and recurrent issue given the fact that new systems are built every time with a constant demand for more efficient machines and for the systems already made new tolerances are imposed. It is also industry aim the rational use of energy in high density energy systems, likewise also is its interest that those systems be robust and self-tunable to operating condition. On that scenario this projects aims to attend those requirements making the use of semi-active devices. A simple semi-active mechanism has been obtained by the association of an elastic element coupled to the main structure through a dry friction joint. This device makes use of the mentioned concept by involving springs activated by a piezoelectric actuator responsible for apply the normal forces at the coupling. Those forces induce friction and consequently introduces variations on systems stiffness, damping and on the apparent mass. In this work such smart spring architecture is studied through a mathematical model with representative characteristics of the mechanism physical properties and also through the test rig developed in the laboratory. The dynamical vibratory system which the device will work is experimentally characterized as well as the contact parameters, tuning the numerical model. It is also described the entire procedure for the device control implementation and is presented control strategies to be used. Finally experimental results of such logics are compared through numerical data, their performances are evaluated and an analysis of their whole performance is presented.