STRUCTURE/MATERIAL CONCURRENT OPTIMIZATION OF LATTICE MATERIALS BASED ON EXTENDED MULTISCALE FINITE ELEMENT METHOD

This paper presents a concurrent optimization technique for structures composed of ultralight lattice materials. The optimization aims at obtaining the minimum structural compliance by optimizing the structural configuration in macroscale and the size of microcomponents of lattice materials concurrently with the specified base material volume. The microstructure of the lattice materials is assumed to be homogeneous to meet the manufacture practice. Optimization in two scales is integrated into one system with the extended multiscale finite element method. In addition, the influences from the finite size of the material microstructures on the optimal results are studied. The superiority of the concurrent optimization relative to the single-scale design of microstructures is indicated. Numerical experiments under linear and periodic boundary conditions validate the proposed optimization model and algorithm.