A Novel Pneumatic Soft Snake Robot Using Traveling-wave Locomotion in Constrained Environments

In this paper we propose a novel pneumatic soft snake robot which exploits traveling-wave motion to move in complex, constrained environments such as a pipeline. The robot is modular, with a unique pneumatic system design that requires the use of only four air channels regardless of the number of modules. The robot is 3D-printed, and thus low-cost and easy to build. Finite element modeling of the bending behavior of each module is conducted in ANSYS. The dynamic behavior of the robot, consisting of six modules, is further modeled in SOFA. In particular, it is found that the locomotion speed of the robot increases with the actuation pressure and decreases with the friction coefficient. Extensive experimental results on a snake robot prototype show good agreements with model predictions. The robot also demonstrates the capability of moving in constrained pipeline environments, including travelling in pipes of different diameters and challenging geometry such as a sharp elbow.