Rubber gas actuator driven by hydrogen storage alloy for in-pipe inspection mobile robot with flexible structure

The authors describe rubber actuators using a hydrogen storage alloy for an in-pipe inspection robot, which is capable of moving inside pipelines with inner diameter as small as 2 in. Rubber actuators with both stretching and shrinking capability are shown for realization of such a robot. The proposed robot uses twelve actuators, including six kinds of independently controlled actuators, so that it si more flexible and adaptable in motion: it can move in an inchworm mode through pipelines, it is adaptive for changing pipe diameters, and it is able to pass over the L- and T-joints of pipelines. The robot actuators can initially be achieved and prepared by hydrogen gas. The control method is also shown, with a T-joint movement as an example