Multi-objective shape optimization of large strain 3D helical structures for mechanical metamaterials

The need for mechanical metamaterials with large strain range and lightweight properties are evidenced to engineering applications. In this regard, novel helical structures proposed as suitable unit cell’s components of metamaterials. Three-dimensional composed varying coil numbers, defined in a cylindrical spatial domain shape optimized through genetic algorithm finite element script conflicting objectives minimum mass maximum tensile range. superior performance the structure is highlighted terms structural rigidity, deformation capability, buckling vibrational modal analysis compare equivalent springs identical weight comparable domain. Deformation mechanism analyzed carefully justify improved performances structure. Tensile compressive experimental undertaken validate enhanced ranges. One dimensional implementations various tessellation arrangements simulated. Results show that design can effectively generate substitutes cells ligaments improve performance. Planar lattice metamaterial concepts employing illustrated demonstrate possibilities promoting integrities