Fuzzy Modal Active Control of Flexible Structures

Abstract

In this paper we propose a new active control strategy to control the dynamic behavior of flexible structures: fuzzy modal control (FMC). This strategy, based on the modal state feedback of the structure, uses independent fuzzy controllers for each mode to be controlled. This method is applied to a flexible beam controlled by a transverse plane of action using piezoelectric actuators. First of all, a model of a piezoelectric actuator is proposed, followed by the formulation of a finite-element model of the mechanical structure/actuator. The model is then fitted using an identification of the characteristics. After modal reduction, the FMC is carried out in two steps: the control of the beam in only one transverse direction by a piezoelectric pusher, then in two transverse directions by two orthogonal piezoelectric pushers located on the same plane. A digital controller was built in the Matlab®-Simulink® environment, and implemented on specialized cards in order to perform the corresponding experiment. The method is validated by comparing the results between the simulation and the experiment.