Vibration control through passive constrained layer damping and active control

To add damping to systems, viscoelastic materials (VEM) are added to structures. In order to enhance the damping effects of the VEM, a constraining layer is attached, creating a passive constrained layer damping (PCLD) treatment. When this constraining layer is an active element, the treatment is called active constrained layer damping (ACLD). Recently, the investigation of ACLD treatments has shown it to be an effective method of vibration suppression. In this paper, the treatment of a beam with a separate active and PCLD element will be investigated. Two new hybrid variations will be introduced. A Ritz-Galerkin approach is used to obtain discretized equations of motion. The damping is modeled using the Golla-Hughes-McTavish (GHM) method and the system is analyzed in the time domain. By optimizing on the performance and control effort for both the active and passive case, it will be shown that hybrid treatment is capable of lower control effort with more inherent damping, and is therefore a better approach to suppressing vibration than ACLD.