Controllable optimal design of auxetic structures for extremal Poisson’s ratio of −2

We develop a lattice structure of a desired Poisson’s ratio that is maintained when subjected to finite deformation . Using a gradient-based design optimization in an isogeometric computational framework, the representative unit cell is sophisticatedly tailored to attain the controlled Poisson’s ratio of up to −2. The ligaments of the lattice structure are modeled using geometrically exact beams whose configuration and cross-sectional area are...