Development of a mobile welding robot for double-hull structures in shipbuilding

This paper describes the development of a selfdriving mobile welding robot. The robot is used to weld U-shaped welding areas in enclosed double-hull structures. In order to place itself inside the double-hull structure, the robot is capable of passing through an access hole 600 mm wide and 800 mm high. This research addresses the mechanical and control systems of the robot. The mechanical system of the robot consists of an eight-axis mobile platform, and a six-axis welding unit. The control system consists of a main controller, a welding machine controller (arc sensor board), and seam tracking sensors, i.e., a touch sensor, a laser sensor, and an arc sensor. To reduce the number of cables that would be dragged by the welding robot, the main controller is designed as an embedded type that is mounted on the back of the mobile platform.