Proposal of One-inch Pipe Inspection Robot “PI-RO I”

Infrastructure pipes require inspection to prevent accidents. However, it is difficult to inspect a 1-in-diameter gas and water pipe because it is long, narrow, and complicated. To inspect 1-in pipe, we have developed pipe inspection robots based on the movement of earthworms or inchworms. However, in either of these robots, one is not able to output high propulsive force, and one is not able to output high traction force. To run and inspect a robot in a complex long-distance pipe, the robot that has both propulsive force and traction force is necessary. In this paper, we propose an active traction type flexible inchworm robot (PI-RO I). The proposed robot has a mechanism that outputs the propulsive force and the traction force actively as a method to make both forces high. To achieve this mechanism, a grip unit for holding the robot inside the pipe and an extension unit for moving the robot were developed, and basic characteristics experiments on these units were conducted. In addition, the propulsive force and the traction force of the robot were measured by running experiments, and it was confirmed that both can output actively.