Development of Parallel Manipulators for Welding Robots

The development of robots for field work is an area where significant efforts are being allocated recently, and the development of new solutions has to fulfil the peculiarities of these tasks. This paper describes the development of a parallel manipulator for a Pipeline Orbital Welding Robot, a one of a kind robot designed to assemble and weld pipelines. It is shown that parallel mechanism can have similar characteristics to serial and prismatic manipulators designs, but without some of its shortcomings, as lack of rigidity, speed and better payload to weight ratio. It is shown in these paper two designs of parallel manipulator that will need to be mounted in the Pipeline Orbital Welding Robot, a small machine that needs to be light, compact and easily attached to the pipe that will be welded. The final objective of the parallel manipulator is to be capable of providing to the robot movements that reproduces the ones from a human welder hand.