Lumped and distributed parameter vibration absorbers for distributed structures

Abstract

The control of low frequency noise and vibration in distributed structures has traditionally been difficult and expensive, because of the long acoustic wavelengths involved. In this paper, conventional technology such as passive, linear, lumped-parameter, dynamic vibration absorbers (DVAs) for distributed structures is introduced first. Then, a new type of active nonlinear distributed-parameter DVAs for distributed structures is investigated. Such absorbers, called Vibration Clamping Absorbers (VCAs), make use of quadraticmodal- positive-position-feedback (QMPPF) control to suppress the vibration of structures at various resonant frequencies. The VCAs can be constructed by using PZT patches driven by a digital signal processor controller. Moreover, the VCAs can control multiple vibration modes by means of a few pairs of sensors and actuators. The effectiveness of the VCA design based on the QMPPF strategy is validated under multiple-mode control on a flexible cantilever beam system with a single sensor-actuator pair. Simulation and experimental results reveal that the proposed strategy is a potentially viable means for active vibration control in distributed structures.