Development of a peristaltic crawling robot for long-distance sewer pipe inspection with consideration of complex pipe line

Sewer pipes play an important role in a city's infrastructure. However, accidents have occurred in recent years due to increasingly old pipes. To prevent such accidents, there is a need to check the internal condition of pipes. Therefore, we focused on the locomotion of a robotic earthworm that is capable of running stably in a narrow space. We developed a peristalsis crawling robot with the goal of traveling 100 m through a 100A pipe. The robot is composed of six unit sections, five joints, and a head section to which the inspection camera is attached. It uses an artificial muscle operated by air pressure. In this study, we developed a new joint to reduce buckling, increase the running speed, and decrease the unit size. Further, we developed a new head section that allowed passage through a 90° elbow pipe. We evaluated the effectiveness of the new robot, and conducted running experiments in horizontal, vertical, and two types of bent pipes.