Genetic algorithm use for internally resonating lattice optimization: Case of a beam-like metastructure

Abstract

Metamaterial inspired structures, or metastructures, are structural members that incorporate periodic or nonperiodic inserts. Recently, a new class of metastructures has been introduced which feature chiral lattice inserts. It was found that this type of inserts has frequency bandgaps which can be tuned by altering the geometry of the chiral lattice. Previous studies have shown that inserting non-periodic chiral lattices inside a beam-like structure results in efficient vibration attenuation at low frequencies. In the study presented in this paper, a genetic algorithm based optimization technique is developed to automatically generate chiral lattices which are tuned to suppress vibration in a flexible beam-like structure. Several parameters are incorporated in the optimization process such as the radius of circular nodes and characteristic angle as well as the spacing and distribution of circular inserts. The efficiency of the proposed optimization technique is verified analytically by numerical simulations. The Society for Experimental Mechanics, Inc. 2016.