Excavation by snake robots with fins and a drill.

In this study, we developed a snake robot composed of fins and a drill to excavate and move underground. In addition, we proposed a method of underground motion using a robot. The underground motion is divided into anchoring and drilling motions. The anchoring motion fixes the robot by anchoring the fins attached to its sides on the tunnel wall using articulated motions. This anchoring motion is required to withstand the reaction forces during the drilling motion and propel the robot. The snake robot has multiple joints; thus it can have various shapes. By changing the shape of the robot, it can accommodate itself to change the tunnel diameter. The drilling motion creates a forward space using the robot's drilling unit. This motion uses the front as well as the sides of the drill for efficient excavation. This reduces the number of insertions and removals, thereby decreasing excavation time. The effectiveness of the anchoring and drilling motions was tested using the robot in an environment simulating an underground tunnel. It was confirmed that the robot could fix, excavate, and withstand reaction forces.