Abstract
Abstract
Embedding active materials into mechanical structures, with the aim of the vibration suppression in the presence of critical excitations and disturbances, which can cause resonant states, represents an important field of research, with significant potentials for the application in the automotive industry. This paper presents the controller design and simulation for the active vibration suppression of a car roof with attached piezoelectric patches used as actuators and sensors. The controller is designed in order to suppress vibrations (which can also be the source of noise) in the presence of periodic disturbances/excitations having the same frequencies as the eigenfrequencies of the car roof. Such disturbances/excitations can cause vibrations in the resonance bandwidth and therefore they should be suppressed or avoided. Suggested controller is an optimal LQ controller with additional dynamics, which includes the knowledge about the frequencies of the excitations which can cause resonant states. For the controller design and simulation a state space model was developed using the finite element method (FEM) approach and the modal reduction. Piezoelectric material was modelled using the Semiloof shell elements, which have mechanical and electrical degrees of freedom. The controller performs significant suppression of the vibration magnitudes in comparison with the uncontrolled case.
Keywords: optimal LQ controller, additional dynamics, vibration suppression, car roof, piezoelectric structure.