Parametric design workflow of periodic lattice structures for additive manufacturing: A case study

With additive manufacturing, greater degrees of design freedoms can be afforded via design optimization and mass customization of part geometries. One way to leverage the geometrical and hierarchical complexities of additively manufactured parts is the manufacturing of functionally-graded lattice structures – a tall order for conventional manufacturing technologies. Yet, the selection of suitable unit cell types and strut diameters to generate lattice structures with desirable mechanical performance for specific applications remains a challenge for engineers due to the lack of computational design support tools integrating domain experts' knowledge and past empirical outcomes across the stages of the engineering design process. This study proposes a digital design workflow which aids decision-making by redefining design features as parametric problems to be solved using algorithmic methods. Using a visual programming application, the 3D model is first parameterized, then fed into a simulation and optimization workflow. Solutions are then generated by iterating all possibilities within the ranges of the design parameters given by the human designer. The methodology presented here is examined through a case study of a bike saddle for fabrication via Multi Jet Fusion, taking into consideration the minimum unit cell gap and minimum strut diameter to ensure the model's printability. Preliminary results indicated that comparisons between different design alternatives can be made easily via the visualization and feedback of the interface. The potential of such an integrated workflow can be further demonstrated in products that can benefit from the mechanical advantages of lattice structures, such as orthotics, personalized sports equipment, and more.