Design and analysis of plate angles of the four-vertex origami pattern and its impacts on movement of rotational joints

Abstract

We present a pneumatic origami joint, which consists of 89 degrees plate angles of Four-vertex origami mechanism activated by pouch motors. The proposed prototype consists of four high-density polyethylene plates connected by flexible adhesive polyethylene tapes. A cutting-binding technique was used for the fabrication of the origami. This technique is inexpensive and easy to replicate. We modeled the kinematics of the origami as a spherical mechanism, and compared with experimental result, against several origami mechanisms with different angles of origami’s plates. We found that an origami mechanism with a plate angle of 89∘ shows around 8.4 times higher rotational movement for a given angular displacement of the input link compared to a mechanism with a plate angle close to 0∘ or a simple fold which is equivalent to a revolute joint. The proposed design is flat-foldable (the sum of odd or even angles around the central vertex equals to 180∘). The pneumatic origami joint can fold and adapt its shape to the environment.