Design of a foldable origami mechanism with helical motion inspired by the Resch Triangular Tessellation

Inspired by artistic origami, researchers in engineering have explored the principles of origami folding to design novel foldable mechanisms, origami robots and metamaterials. Taking inspiration from the Resch Triangular Tessellation, an artistic origami of which the central triangular panel twists during the folding/unfolding process, this paper presents a novel origami mechanism with a foldable/deployable form. It has 3-Degrees-of-Freedom (DoFs) and is capable of helical motion (one twisting motion coupled with the translation along with the same axis). The mechanism is composed of two minimum units of the Resch Triangular Tessellation pattern connecting in stack face to face. Three origami creases intersecting at a common point, equivalent to a traditional spherical joint, are adopted for the connection. The geometric and kinematic characteristics of the origami mechanism are analyzed. The workspace of the moving platform of the mechanism is analyzed. A proof-of-concept prototype of the mechanism is fabricated and experimentally demonstrated by a cable-driven actuation system. The pure helical motion mode (when three inputs are the same) is tested using the prototype and is compared with the theoretical model. Diverse motion configurations with different settings of input angles are presented by evaluating the 3D model and prototype of the novel helical mechanism. The connection of multiple helical origami mechanisms in series leads to a novel continuum robot which is also discussed. Compared with other counterparts, the novel mechanism has both the helical motion and origami-like foldability without needing flexible panels.