A Soft Growing Robot Using Hyperelastic Material

Abstract

Soft growing robots have received considerable attention because of their unique locomotion. However, the use of a single material for their manufacturing causes numerous problems, because each part of the robot requires different characteristics. This study attempts to solve this fundamental problem from a material perspective, rather than integrating independent solutions. A hyperelastic material is proposed for building a soft growing robot. Several problems associated with conventional soft growing robots are addressed using a hyperelastic material that offers the required properties for each part of the soft growing robot, while maintaining its intrinsic advantages. Two unique features of hyperelastic materials, bulging and shape‐locking, are introduced. The advantages that these two features offer to soft growing robots are investigated and analyzed. A soft growing robot, utilizing these features, can easily achieve shape locking, small tail tension, easy retraction, uniform circular inner channel, and wrinkle‐free curve formation, without additional hardware. The initial concept of the growing and steering mechanisms of a hyperelastic soft growing robot is proposed and demonstrated using a prototype.