Abstract

The additive manufacturing industry continues to grow with new machines, faster processes and a large selection of materials. Design practitioners are now enabled to unleash the full potential of AM with the use of Generative Design and Lattice structures. Generative Design is the automatic process of generating optimum feasible designs from a set of performance requirements and design rules. With the use of manufacturing constraints, the generated organic designs can be printed using additive manufacturing. Generative Design is a fundamentally disruptive paradigm shift. Over the last 3000 years humans conceived a design and then built physical or virtual prototypes to evaluate the design’s performance requirements. Generative Design spawns designs that even experienced skilled practitioners couldn’t imagine. There is no preconceived geometry as a starting point. The geometric complexity of these designs can be handled by additive manufacturing. Lattice structures are topologically ordered, three-dimensional open-celled structures that are used by nature. An example of exceptional achievement of evolutionary engineering is the formation of the biphotonic gyroid material in butterfly wings. Visually stunning manifestations of light weight biological nanostructured materials are observed in insects, birds, and plants. Lattice structures are very effective for lightweight structural panels, energy absorption devices, thermal insulation, high performance heat exchangers, ballistic protection and porous implants. The combination of Generative Design tools and Lattice structures is producing a tsunami of change in the design process. This presentation will demonstrate this new design process with an example of light weighting a helicopter bell crank. The baseline component is examined for stress compliance and the design space is established without interference during the mechanism motion. The Generative Design procedure uses homogenized material properties, of the lattice structure, and establishes the optimized topology. This topology is filled with a Stochastic Lattice structure. The density and size of the struts can be driven by the three-dimensional stress field of the optimized topology. Experimental results of the optimized topology will be also presented.