Aerospace vehicles utilize slender, high-aspect ratio structures with small material volume fractions to achieve high stiffness-to-mass and strength-to-mass ratios. Optimization of these structures using topology optimization is challenging due to the demanding mesh requirements and large size of the design problem which scales in proportion to the analysis problem. We have addressed these difficulties by using a scalable framework for analysis and design of large-scale topology and multimaterial optimization problems. This framework includes a multigrid method for solving large structural finite-element problems, and a parallel design optimization framework for solving large-scale optimization problems.

The video above shows the convergence history of a large multimaterial structural optimization problem solved using both parallel analysis and parallel design optimization methods developed by our group. The solution of this large-scale design problem would not be possible within a practical time frame without the efficient use of high-performance parallel computing resources.To make this design into a physical structural component, we can use additive manufacturing, also known as 3D printing. In this case, we remove the specification of different materials, and concentrate on the manufacturing process with the given geometry. To manufacture the structure, we create a representation of the model that is compatible with additive manufacturing tools. For this purpose, we generate an .stl file in a post processing step from the voxel-based description of the structure used during optimization. More information on the .stl file format can be found here. After this post-processing step, the part can be manufactured using additive manufacturing techniques. Thanks to Justin Gray for printing this sample part!

The objective of this research is to close the gap between methods used to parametrize the structure for design optimization and the manufacturing process itself in order to achieve higher-performance structures that meet all design requirements.