Motion Design for a Snake Robot Negotiating Complicated Pipe Structures of a Constant Diameter

A method for designing the motion of a snake robot negotiating complicated pipe structures having a constant diameter is presented. For such robots moving inside pipes, there are various "obstacles" such as junctions, bends, shears, and blockages. To surmount these obstacles, we propose a method that enables the robot to adapt to multiple pipe structures of a constant diameter. We designed the target form of the snake robot of two helices connected with an arbitrary shape. This method is applicable to various obstacles by designing a part of the target form conforming to the obstacle. The robot negotiates obstacles under shift control by employing a rolling motion. We demonstrated the effectiveness of the proposed method in various experiments.