Development of a steerable in-pipe locomotive device with six braided tubes

Numerous studies have developed in-pipe locomotive devices to inspect pipes. However, it is difficult to achieve selective locomotion in a branched piping system. In this study, a novel steerable in-pipe locomotive device is proposed based on “a six-braided-tubes locomotive device,” which is an in-pipe locomotive device that is actuated by only six pneumatic inflatable tubes. It is one of the simplest in-pipe locomotive devices that is capable of forward and backward motion and can rotate in clockwise and counterclockwise directions along a pipe, can select the desired pathway in the branched pipe. In this paper, we discuss the background of pipe inspection, classify previously developed in-pipe locomotive devices, and clarify the aim of this study. Additionally, we also describe and extend the locomotive principles of six-braided-tubes locomotive devices. Moreover, we propose a novel attachment, termed steering hook, to enable steering in various types of branched systems. Finally, we experimentally confirm that the novel proposed principle allows the device to correct path selection in an in-pipe branched piping system.