VIBRATION REDUCTION USING A NONLINEAR ATTACHMENT INCLUDING AN ACTIVE DAMPER WITH DELAY

摘要

This paper presents the interest of a nonlinear passive absorber coupled to a semi-active damper with delay for vibration isolation of harmonic disturbances. The passive absorber consists of an essentially nonlinear oscillator (nonlinear energy sink [NES]), having the task to transfer the energy from the main structure to the semi-active device. The semi-active device consists of an active viscous damper with semi-active strategy control including delay. A theoreticalumerical analysis based on complexification and averaging methods together with multipe scale method is performed. It is shown that the approach is able to predict the behaviour of the system including time delay. The influence of the time delay on the efficiency of semi-active nonlinear absorber is studied. It is shown that time-delay could be used as a design parameter to improve the control of the vibration of the primary system suppressing strongly modulated regimes through periodic regimes.