Origami-Patterned Rigidification for Soft Robotic Bifurcation

Abstract

The fluid-transportation functions based on the volume-regulating behavior of the chamber-like organs inspire the development of artificial organs. Due to the intrinsic compliance of soft robotics for biomimicking purposes and the volume-regulation capability of the 3D origami patterns, the soft robots with origami patterns show promising potential in such research. However, the folding deformation of the origami facets cannot be straightforwardly implemented as the actuation or the body movement, and the predetermined movements of the pattern limit the appropriate functions for specific applications. In this work, an origami-patterned rigidification (OPR) method is proposed for applying rigid origami mechanisms (herein, the cuboctahedron origami ball) to the chamber-like structure of soft robots. The motion of the soft robot is programmed by purposefully rigidified the soft chamber following the pattern. The resultant OPR structures are granted with functions corresponding to the predetermined motion of the pattern, and the expanded movements through the bifurcation brought by the soft–rigid characteristics. The concept, design, and fabrication of the OPR robot are presented. By analyzing the deformation of the soft creases, the kinematic models of the predetermined and expanded degrees of freedom are presented and verified by experiments. The extended functions of two OPR robots are demonstrated.