Vibration Analysis of Lattice Structures with Negative Poisson's Ratio

Poisson’s ratio is the negative of the ratio of (signed) transverse strain to (signed) axial strain. For small values of these changes, Poisson’s ratio is the amount of transversal expansion divided by the amount of axial compression. Although most of materials in life show positive Poisson’s ratio, there are artificial structures which show negative Poisson’s ratio. There are few researches about the dynamic characteristics of these structures, so in our research, we analysis the vibration modes in the field of micro deformation and found out that one additional zero mode showed up compared with structures with positive Poisson’s ratio.