Design of a Tractor-Trailer Climbing Robot for Large Pressure Vessel Inspection

In-service large pressure vessels need periodic inspection to keep safe operation. Inspection robot for large pressure vessel needs adaption to curved surface, multifunctional and heavy load abilities. In this paper, a tractor-trailer type climbing robot is designed to meet the requirement. The constitutes of robot is introduced. By mutual reference of weld data identified from vision and known weld line distribution map, the approaches of robot self-location and weld line distinguishing are given. An output limited PID controller is designed for weld seam tracking. Experiments show that the robot can carry different tools and automatically track weld lines on the surface of large pressure vessels.