Programmable Soft Robotic Materials via Rotational Multimaterial 3D Printing

The rapid design and fabrication of soft robotic materials is of growing interest for shape-morphing, actuating, and wearable devices. Here, we have developed a method to parameterize and programmatically print soft robotic materials via rotational multimaterial 3D printing. Specifically, we pattern asymmetrical core-shell filaments in both 1D and 2D motifs, which are composed of an elastomeric shell and a fugitive core that serve as fluidic actuators. Our fabrication process allows precise control over the print path as well as pneumatic channel orientation, shape, and volume along each filament. We employ an automated Fermat spiral pathing approach to automatically path 2D designs by combining known curvature responses and relative resolution on surface actuators. This pathing method enables localized property assignment and design iteration through an interactive online code repository. Our integrated design and printing approach allows one to programmably generate soft robotic matter with complex shape morphing behavior on demand.