Design and Analysis of a Square-shaped Continuum Robot with Better Grasping Ability

Continuum robots, often taking inspiration from biomimetics, are an exciting novel research field and have a great capability. New continuum robots can be inspired by biologies such as seahorses, pipefish, and pipehorses, which have both strong skeleton and great dexterity. In this paper, the main idea contained is how to effectively employ the square components, which aim to imitate the armor and to connect the square components with the ball pairs and soft surface. For displaying the dexterity features of the square continuum robot (SCR), both the bending and twisting capabilities were studied. Meanwhile, a comparison was also considered in order to validate and analyze the dexterity differences in the numerical model, skeleton prototype, and SCR. The static characters of the SCR were shown both numerically and experimentally so that the mechanical properties are clear. Then, impact experiments were carried out to demonstrate the cushion effect. In addition, the maximum grasping load was also determined to quantize the grasping capability. Finally, a robot system was developed to handle objects with various shapes. Our results reveal that the SCR connected by the soft surface has improved flexibility, cushion stability, and better-grasping capability, with some loss of dexterity compared to SCR's skeleton.