Environment Modeling for Autonomous Welding Robots

Automation of welding process in shipyard is ultimately necessary, since welding site is spatially enclosed by floors and girders, and therefore welding operators are exposed to hostile working conditions. To solve this problem, a welding robot that can navigate autonomously within the enclosure needs to be developed. To achieve the welding task, the robotic welding system needs a sensor system for the recognition of the working environments and the weld seam tracking, and a specially designed environment recognition strategy. In this paper, a three-dimensional laser vision system is developed based on the optical triangulation technology in order to provide robots with work environmental map. At the same time, a strategy for environmental recognition for welding mobile robot is proposed in order to recognize the work environments efficiently. The design of the sensor system, the algorithm for sensing the structured environment, and the recognition strategy and tactics for sensing the work environment are described and dis- cussed in detail. I. Introduction At shipyards, the demands of automatic operations and the desire to pursue a broader automation strategy have fueled the development of new advanced robotic and process control systems. Due to the increase of personnel expenses, the auto- mation of the welding process is necessary for improving the productivity and quality of shipbuilding process. In shipbuild- ing, a key aspect of the welding process automation is the prefabrication of sub -assemblies on automated lines using robotic welding technology. The welding process for the sub- assembly consists of an open-block welding and an closed -