A pixel design method for mechanical metamaterials based on topology optimization

Mechanical metamaterials attract a lot of interest because of the peculiar mechanical properties. Especially in adjustment of Poisson's ratio of structures, the auxetic mechanical metamaterials have shown their outstanding advantages. Some topology optimization methods are also used to optimize the auxetic structures. In this article, we propose a pixel design method for mechanical metamaterials arrangement based on topology optimization. Metamaterials optimized with two different objectives: the maximum stiffness (MS) and the maximum stiffness with minimum Poisson's ratio (MSMP) are obtained by this method. The lattice of the metamaterial is in uniform size and its stiffness can be adjusted. The topology optimization is used to achieve the optimal stiffness distribution of the design area. Then, the stiffness distribution is pixelated according to the lattice size. The required metamaterials can be achieved by filling the lattice structure into this pixel image. The experimental results are consistent with the simulation.