Design and Fabrication of Silicone Kirigami-inspired structures for Soft Robotic Applications

Recent advances in soft robotics and wearable devices have inspired researchers to explore other fields, such as kirigami, origami, and tensegrity structures, for innovative solutions. Kirigami, the Japanese art of making patterned cuts in a sheet, allows flat or rigid materials to transform into flexible structures with unique mechanical properties, giving rise to metamaterials. Traditional fabrication methods, such as blade cutting, are laborious and time-consuming, whereas laser cutting and photolithography require special environments for operation. This work proposes a direct approach to design and fabricate closed-loop kirigami structures, eliminating the need for cuts by distributing the geometry strategically. To streamline the design-to-fabrication process, kirigami structures with varying mechanical properties were developed using a Python-based parametric design tool. This tool generated continuous toolpath G-codes for Direct Ink Writing (DIW) with elastomeric RTV silicones. The potential to transform flat 2D geometries into volumetric 3D shells is demonstrated through an in-depth design space exploration, FEA simulations, and the fabrication process. This research focuses on flat polygonal shape primitives segmented into concentric contours and placing connecting hinges at different offset angles. These easily fabricated elastomeric kirigami structures hold great potential for applications in soft robotics, wearable technologies, and kinetic installations.