Abstract: For the container ripple line fillet seams tracking, it is necessary not only to control welding-torch moving along with the seams, but also to adjust inclination of the the torch perpendicular to the welding surface.In this paper, a wheeled mobile welding robot with a cross-slider manipulator that can extend and turn was developed.A rotational arc sensor was used to detect the welding-torch deviations and inclinations simultaneously.Through controlling three joints coordinate movement, welding seam tracking and welding-torch inclination adjusting were achieved.The kinematics model of the mobile robot is established, and with fuzzy control theory, a controller was designed.Through actual welding experiments, the validity of the proposed method is proved.