OPTIMIZATION OF STRUCTURES FOR 3D PRINTING AND ADDITIVE MANUFACTURING

Lattice-enforced shell structures are frequently used in lightweight construction, since they combine high stiffness with low weight. Modern production methods like 3D printing open for new methods of the fabrication of optimized structures by overcoming almost all limitations of traditional manufacturing procedures. In this project several methods for the optimization of mechanical structures will be compared.  In the first part of the investigation, the structural advantages obtained with structural lattice sizing optimization for standard design responses as stiffness and mass are explored. In this part, a baseline structure resulting from a traditional structural continuum topology optimization is applied. Those results are compared to the structural advantages of designs using a hybrid sequential optimization approach. The optimization structure is consisting of 3 phases: traditional solid material phase (continuum topology optimization), traditional lattice structural members (sizing optimization) and voids representing holes. The hybrid approach was applied on static analyses of initially various 2D academic cases for testing various optimization concepts. Finally, a combined sizing optimization was developed, for simultaneously optimizing the shells (thickness) and lattices (radius of beams). Here the interesting design issue was to see if the optimizer is trying to optimize against a shell like structure, a lattice like structure or a hybrid solution combining a shell and a lattice structure.