Multi material topological optimization of structures and mechanisms

Multi-material 3D-printing technologies permit the freeform fabrication of complex spatial arrangements of materials in arbitrary geometries. This technology has opened the door to a large mechanical design space with many novel yet non-intuitive possibilities. This space is not easily searched using conventional topological optimization methods such as homogenization. Here we present an evolutionary design process for three-dimensional multi-material structures that explores this design space and designs substructures tailored for custom functionalities. The algorithm is demonstrated for the design of 3D non-uniform beams and 3D compliant actuators.