Creating a flexible continuum robot using origami and mortise-tenon structure

The continuum robot is a bionic robot with infinite freedom and adaptability to unstructured environments. This paper creates a flexible continuum robot using origami and mortise-tenon structure (FCROM) to explore the feasibility of making a continuum robot using thin plates. The process of making an FCROM is described in detail, and a modular joint of the FCROM is analyzed using the 3D chain pseudo-rigid body model (3D-CPRBM) and the finite element method. Then several improved joints are proposed to solve the issue of axial drift for the modular joint. The performance of these improved joints is compared and analyzed, and then an improved joint is selected as the basic joint of the FCROM. A simplified model is built and solved to capture the rotation angle of the FCROM better. The FCROM with three joints is tested experimentally, and the result shows that the robot can achieve bending motion correctly. The rotation angles obtained from the simplified model and the experimental test are almost consistent, with an error of about 8%. Finally, some problems encountered during the design and fabrication of the FCROM are discussed, and some corresponding suggestions are given.