Abstract
This paper describes a composition of an articulated multi-vehicle robot in pipe, structure of each vehicle, and their control systems. Output pressure versus extension characteristic of the newly developed two-stage air cylinder, reduction of the wave reflection in a wheel-type ultrasonic probe, umbilical cable assembly housing optical fibers, air tubes and electric cables are treated. The articulated robot is designed and fabricated to demonstrate its travelling performance and automatic scanning of five probes for non-destructive test of a weld bead to the longitudinal direction. The results show that the robot can travel in the pipe of radius 520-800 [mm∅] from its entrance to the distance 150 [m] . The robot can pick up surrounding color images and transmit them to the ground station's monitor with sharpness. Also, the NDT is shown to be possible except in the vicinity of elbow area of the pipe.
