OPTIMUM DESIGN AND CONTROL OF ACTIVE CONSTRAINED LAYER DAMPING

Conventional Passive Constrained Layer Damping (PCLD) treatments with viscoelastic cores are provided with built-in sensing and actuation ca pabilities to actively control and enhance their vibration damping cha racteristics. The design parameters and control gains of the resulting Active Constrained Layer Damping (ACLD) treatments are optimally sele cted, in this paper, for fully-treated beams using rational design pro cedures. The optimal thickness and shear modulus of the passive visco- elastic core are determined first to maximize the modal damping ratios and minimize the total weight of the damping treatment. The control g ains of the ACLD are then selected using optimal control theory to min imize a weighted sum of the vibrational and control energies. The theo retical performance of beams treated with the optimally selected ACLD treatment is determined at different excitation frequencies and operat ing temperatures. Comparisons ave made with the performance of beams t reated with optimal PCLD treatments and untreated beams which are cont rolled only by conventional Active Controllers (AC). The results obtai ned emphasize the potential of the optimally designed ACLD as an effec tive means for providing broad-band attenuation capabilities over wide range or operating temperatures as compared to PCLD treatments.