A Soft Hybrid-Actuated Continuum Robot Based on Dual Origami Structures

Soft continuum robots have shown tremendous potential for medical and industrial applications owing to their flexibility and continuous deformability. However, their telescopic and bending capabilities and variable stiffness are still limited. This study proposes a novel origami-inspired soft continuum robot to possess large telescopic and bending capabilities while improving stiffness based on the principle of antagonistic actuation. The soft robot consists of dual origami structures. The inner forms an air chamber actuated by pneumatics, and the outer is controlled by nine tendon-driven actuators. The proposed design uses the advantages of a hybrid actuation to achieve motion and stiffness control. The performance of the soft robot is studied experimentally based on single and three robot modules. Results show that the robot has an excellent stretch ratio and a maximum bending angle of 180°. The robot can also increase stiffness to resist the bending deformation induced by self-weight and loads.