20701 A Study on Pneumatic Actuators for Green Caterpillar type In-Pipe Mobile Robots

We have many small diameter pipes that are gas or water pipes for individual or corporate houses. They must be periodically inspected in order to protect the accident previously. We have proposed an in-pipe mobile robot that is imitated the waving motion of the green caterpillar. The robot is constructed by two somites and three suction brakes. The somites are imitated the waving motion driven by the pneumatic and the vacuum pressures. The robot was confirmed to move in pipes whose diameters are more than 70 mm. The robot is needed the large traction force in the case of the long pipe movement, because it must tow the pressure lines. Now, we investigated the traction force from the mechanisms of the robot. The traction force depended on the friction force of the suction brake and shrinking force of the somite. It was obtained 31 N.